{"url_path":"/sec/nmr/10-k/2026/cover-page","section_key":"cover-page","section_title":"Cover Page","topic":"sec","document":{"doc_type":"20-F","doc_date":"2026-06-22","source_url":"https://www.sec.gov/Archives/edgar/data/1163653/0001193125-26-277134-index.html","accession_number":"0001193125-26-277134","cik":"0001163653","ticker":"NMR","issuer_name":"NOMURA HOLDINGS INC","edgar_url":"https://www.sec.gov/Archives/edgar/data/1163653/0001193125-26-277134-index.html","primary_entity_key":"0001163653","primary_entity_name":"NOMURA HOLDINGS INC"},"word_count":14178,"has_tables":true,"body_markdown":"Annual Report\n\n##### Table of Contents\n\nfalseFY0001163653Includes primarily personnel expenses, occupancy, technology, and professional fees.Includes the amount of embedded derivatives bifurcated in accordance with ASC 815.Represents amounts which are not permitted to be offset on the consolidated balance sheets in accordance with ASC 210-20 and ASC 815 but which provide Nomura with a legally enforceable right of offset in the event of counterparty default. Amounts relating to derivative and collateral agreements where Nomura has not yet obtained sufficient evidence of enforceability of such offsetting rights are excluded. As of March 31, 2025, a total of ¥343 billion of cash collateral receivables and ¥1,043 billion of cash collateral payables, including amounts reported in the table, have not been offset against net derivatives. As of March 31, 2026, a total of ¥399 billion of cash collateral receivables and ¥1,300 billion of cash collateral payables, including amounts reported in the table, have not been offset against net derivatives.Net derivative assets and net derivative liabilities are generally reported within Trading assets and private equity and debt investments—Trading assets and Trading liabilities, respectively in the consolidated balance sheet. Bifurcated embedded derivatives are reported within Short-term borrowings or Long-term borrowings depending on the maturity of the underlying host contract.Represents amounts offset through counterparty offsetting of derivative assets and liabilities as well as cash collateral offsetting against net derivatives under master netting and similar agreements for which Nomura has obtained sufficient evidence of enforceability in accordance with ASC 210-20 and ASC 815. As of March 31, 2025, Nomura offset a total of ¥1,740 billion of cash collateral receivables against net derivative liabilities and ¥2,090 billion of cash collateral payables against net derivative assets. As of March 31, 2026, Nomura offset a total of ¥2,035 billion of cash collateral receivables against net derivative liabilities and ¥2,416 billion of cash collateral payables against net derivative assets.Includes all gross derivative asset and liability balances irrespective of whether they are transacted under a master netting agreement or whether Nomura has obtained sufficient evidence of enforceability of the master netting agreement. As of March 31, 2025, the gross balance of derivative assets and derivative liabilities which are not documented under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability was ¥609 billion and ¥832 billion, respectively. As of March 31, 2026, the gross balance of such derivative assets and derivative liabilities was ¥1,027 billion and ¥1,206 billion, respectively.Carrying value amounts are shown on a gross basis prior to cash collateral or counterparty offsetting. Asset balances represent positive fair value amounts caused by tightening of credit spreads of the underlyings since inception of the credit derivatives.There is no revenue derived from transactions with a single major external customer.Weighted-average price of NHI shares used to determine the final cash settlement amount of the awards.Weighted-average price of NHI shares used to determine number of awards granted.The price of NHI shares used to remeasure the fair value of the remaining outstanding unvested awards as of March 31, 2025.Other includes credit derivatives where the credit rating of the underlying reference asset is below investment grade or where a credit rating is unavailable.Includes net gains (losses) on derivatives used for non-trading purposes which are not designated as fair value or net investment hedges. For the year ended March 31, 2024, 2025 and 2026, net gains (losses) for these non-trading derivatives were not significant.Includes a reversal of unrealized gain (loss) on investments in equity securities held for operating purposes that were sold in the years ended March 31, 2024, 2025 and 2026.Primarily includes an increase of ¥12,691 million of valuation allowances on deferred tax assets primarily related to valuation of financial instruments of certain foreign subsidiaries. While valuation allowances on deferred tax assets of foreign subsidiaries related to operating loss carryforwards had increases due to foreign exchange, valuation allowances of certain foreign subsidiaries had decreases in operating loss carryforwards due to utilization by improved profitability, resulting in an immaterial net change during the year. In addition, there was an increase of ¥4,718 million of valuation allowances on deferred tax assets related to Japanese subsidiaries and the Company primarily due to an increase of valuation allowances of Investments in subsidiaries and affiliates. In total, ¥17,409 million of allowances increased.Primarily includes a decrease of ¥21,610 million of valuation allowances on deferred tax assets of certain foreign subsidiaries primarily due to a decrease in operating loss carryforwards, and a reduction of ¥3,041 million of valuation allowances on deferred tax assets related to Japanese subsidiaries and the Company primarily due to a utilization of loss carryforwards. In total, ¥24,651 million of allowances decreased.Primarily includes an increase of ¥83,838 million of valuation allowances on deferred tax assets of certain foreign subsidiaries primarily due to an increase in operating loss carryforwards, and a reduction of ¥3,238 million of valuation allowances on deferred tax assets related to Japanese subsidiaries and the Company primarily due to a utilization of loss carryforwards. In total, ¥80,600 million of allowances increased.Repurchase agreements and securities lending transactions are reported within Collateralized financing—Securities sold under agreements to repurchase and Collateralized financing—Securities loaned in the consolidated balance sheets, respectively. Amounts reported for securities lending transactions also include transactions where Nomura lends securities and receives securities that can be sold or pledged as collateral. Nomura recognizes the securities received at fair value and a liability for the same amount, representing the obligation to return those securities. The securities received and the liability are reported within Other assets-Other and Other liabilities in the consolidated balance sheets, respectively. The total gross recognized liabilities reported for repurchase agreements and securities lending transactions are consistent with the total gross balances reported in the offsetting disclosures above.Includes ¥3,586 billion of U.S. government sponsored agency mortgage pass through securities and collateralized mortgage obligations as of March 31, 2025. Includes ¥2,877 billion of U.S. government sponsored agency mortgage pass through securities and collateralized mortgage obligations as of March 31, 2026.Includes financial instruments which are carried at fair value on a recurring basis.The amounts of write offs for the year ended March 31, 2025 were not significant.Amounts are presented by calendar year of origination.The amounts are aggregated by reference to the year in which the contract became effective, rather than the date of loan drawdown.Relates to collateralized exposures where a specified ratio of LTV is maintained.Amounts are presented by fiscal year of origination.The amounts of write offs for the year ended March 31, 2026 were not significant.Nomura recognized goodwill in December 2025 as a result of the Macquarie Acquisition. See Note 10 “Business Combinations” for further information.Client relationships as of March 31, 2026 include intangible assets with a net carrying value of ¥112,659 million as of March 31, 2026 related to the Macquarie Acquisition described in Note 10 “Business Combinations” to the consolidated financial statements, weighted average amortization period for the corresponding intangible assets is 12 years.Includes currency translation adjustments.The impairment recognized during the current period was not a significant amount.Derivatives which contain multiple types of risk are classified based on the primary risk type of the instrument.Open transactions do not have an explicit contractual maturity date and are terminable on demand by Nomura or the counterparty.Consideration of the interrelationships between significant unobservable valuation inputs is only relevant where more than one unobservable valuation input is used to determine the fair value measurement of the financial instrument.Includes non-financial assets carried at fair value on a recurring basis.Valuation techniques and unobservable valuation inputs in respect of equity securities reported within Other assets in the consolidated balance sheets.Items recognized as bearing substantially the same obligation of a guarantee of liabilities are included in this note.Includes joint guarantees with Nomura International (Hong Kong) Limited.Includes joint guarantees with Nomura Securities Co., Ltd.Range information is provided in percentages, coefficients and multiples and represents the highest and lowest level significant unobservable valuation input used to value that type of financial instrument. A wide dispersion in the range does not necessarily reflect increased uncertainty or subjectivity in the valuation input and is typically just a consequence of the different characteristics of the financial instruments themselves.Weighted average information for non-derivatives is calculated by weighting each valuation input by the fair value of the financial instrument.Nomura has not provided weighted average information for derivatives as unlike cash products the risk on such products is distinct from the balance sheet value and is subject to netting. Discussion of the ranges of significant unobservable valuation inputs for derivatives and short-term and long-term borrowings which contain embedded derivatives classified in Level 3 is provided below as a substitute for weighted average information.No allowances for credit losses have been recognized as of March 31, 2025 and 2026.Net deferred tax assets are deferred tax assets offset by deferred tax liabilities which relate to the same tax-paying component within a particular tax jurisdiction. Net deferred tax liabilities are deferred tax liabilities offset by deferred tax assets which relate to the same tax-paying component within a particular tax jurisdiction. See Note 17 “Income taxes” for further information.See Note 2 “Fair value measurements” for further information.See Note 15“Employee benefit plans” for further information.See Note 6 “Non-trading investments” for further information.Include all recognized balances irrespective of whether they are transacted under a master netting agreement or whether Nomura has obtained sufficient evidence of enforceability of the master netting agreement. Amounts include transactions carried at fair value through election of the fair value option. As of March 31, 2025, the gross balance of reverse repurchase agreements and repurchase agreements which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability amounted to ¥441 billion and ¥1,973 billion, respectively. As of March 31, 2025, the gross balance of securities borrowing transactions and securities lending transactions which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability amounted to ¥1,528 billion and ¥111 billion, respectively. As of March 31, 2026, the gross balance of reverse repurchase agreements and repurchase agreements which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability amounted to ¥458 billion and ¥895 billion, respectively. As of March 31, 2026, the gross balance of securities borrowing transactions and securities lending transactions which were not transacted under master netting agreements or are documented under master netting agreements for which Nomura has not yet obtained sufficient evidence of enforceability amounted to ¥1,532 billion and ¥151 billion, respectively.Represent amounts which are not permitted to be offset on the face of the consolidated balance sheets in accordance with ASC 210-20 but which provide Nomura with the right of offset in the event of counterparty default. Amounts relating to agreements where Nomura has not yet obtained sufficient evidence of enforceability of such offsetting rights are excluded.Represent amounts offset through counterparty netting under master netting or similar agreements for which Nomura has obtained sufficient evidence of enforceability in accordance with ASC 210-20. Amounts offset include transactions carried at fair value through election of the fair value option.Reverse repurchase agreements and securities borrowing transactions are reported within Collateralized agreements—Securities purchased under agreements to resell and Collateralized agreements—Securities borrowed in the consolidated balance sheets, respectively. Repurchase agreements and securities lending transactions are reported within Collateralized financing—Securities sold under agreements to repurchase and Collateralized financing—Securities loaned in the consolidated balance sheets, respectively. Amounts reported under securities lending transactions also include transactions where Nomura lends securities and receives securities that can be sold or pledged as collateral. Nomura recognizes the securities received at fair value and a liability for the same amount, representing the obligation to return those securities. The securities received and the liability are reported within Other assets—Other and Other liabilities in the consolidated balance sheets, respectively.Transfers into Level 3 indicate certain valuation inputs of a financial instrument become unobservable or significant. Transfers out of Level 3 indicate certain valuation inputs of a financial instrument become observable or insignificant. See “Quantitative and qualitative information regarding significant unobservable valuation inputs” above for the valuation inputs of each financial instruments.Transfers out of Level 3 include financial instruments that moved out of level 3 by application of measurement alternative. See Note 6 “Non-trading investments” for further information of financial instruments under the measurement alternative.Includes gains and losses reported within Net gain on trading, Gain on private equity and debt investments, and also within Gain(loss) on investments in equity securities, Revenue—Other and Non-interest expenses—Other, Interest and dividends and Interest expense in the consolidated statements of income.Amounts of gains and losses on these transfers which were recognized in the period when the Transfers into Level 3 occurred were not significant for the years ended March 31, 2025 and March 31, 2026.The range in prior notice period for redemption.The contractual amount of any unfunded commitments Nomura is required to make to the entities in which the investment is held.The frequency with which Nomura is permitted to redeem investments.Amounts reported in Purchases / issues include increases in trading liabilities while Sales / redemptions include decreases in trading liabilities.The impact of an increase in the significant unobservable valuation input on the fair value measurement for a derivative assumes Nomura is long risk to the input (such as being long volatility). Where Nomura is short such risk, the impact of an increase would have a converse effect on the fair value measurement of the derivative.The above table only considers the impact of an increase in each significant unobservable valuation input on the fair value measurement of the financial instrument. However, a decrease in the significant unobservable valuation input would have the opposite effect on the fair value measurement of the financial instrument. For example, if an increase in a significant unobservable valuation input would result in a lower fair value measurement, a decrease in the significant unobservable valuation input would result in a higher fair value measurement.Includes corporate type equity investments.Includes primarily debt investment funds. Hedge funds and real estate funds are also included.Certain plan assets that are carried at fair value using net asset value per share as a practical expedient have not been classified in the fair value hierarchy. As of March 31, 2025 and 2026, the fair value of these assets was ¥35,529 million and ¥38,092 million, respectively.Includes unrealized gains and losses of ¥10 billion and ¥(1) billion for the years ended March 31, 2025 and 2026 recognized in Other comprehensive income (loss) for recurring Level 3 fair value measurements held at the end of the reporting period.Carrying values are shown after deducting relevant allowances for credit losses.Represents the amount offset under counterparty netting of derivative assets and liabilities as well as cash collateral netting against net derivatives assets or liabilities.Dividends from affiliate for which FVO was elected are reported within Interest and Dividends.Equity in earnings of equity-method investees is reported within Revenue—Other in the consolidated statements of income.Includes collateralized loan obligations (“CLOs”) and asset-backed securities (“ABSs”) such as those secured on credit card loans, auto loans and student loans.Non-trading debt securities are primarily Japanese municipal securities issued by prefectures or ordinance-designated city.Investments in and advances to affiliated companies comprise shares in Nomura Research Institute, Ltd.On April 10, 2025, Nomura sold certain owned land and buildings located in Takanawa 2-chome, Minato-ku, Tokyo, for the effective utilization of its assets. The transaction counterparties included Nomura Real Estate Development Co., Ltd., a subsidiary of Nomura Real Estate Holdings, Inc., an affiliated company, and a third party financing company. Nomura considers the entire transaction to be with a related party. As a result of the sale, a gain of ¥56,144 million is included in Revenue—Other in the consolidated statements of income for the year ended March 31, 2026.Includes the impact of Nomura’s own creditworthiness.Credit derivatives are disclosed in Note 3 “Derivative instruments and hedging activities” and are excluded from above.Derivative contracts primarily consist of equity, interest rate and foreign exchange contracts. Primarily related to a certain sponsored repo program where Nomura guarantees to a third party clearing house in relation to its clients’ payment obligations. Our credit exposures under this guarantee is minimized by obtaining collateral from clients at amount approximately the maximum potential payout under the guarantee.Cost, accumulated depreciation and net carrying amounts include amounts relating to real estate used by Nomura.Includes secured borrowings of ¥472,328 million and ¥670,182 million as of March 31, 2025 and March 31, 2026 respectively.Includes secured borrowings of ¥811,118 million and ¥720,958 million as of March 31, 2025 and March 31, 2026 respectively.Includes secured borrowings of ¥119,682 million and ¥113,315 million as of March 31, 2025 and March 31, 2026 respectively.Primarily due to improved profitability and increase in taxable temporary differences resulted in release of certain valuation allowance.Includes gains and losses reported primarily within Net gain on trading, Gain on private equity and debt investments, and also within Gain (loss) on investments in equity securities, Revenue—Other and Non-interest expenses—Other, Interest and dividends and Interest expense in the consolidated statements of income.The tax effects in this category primarily relate to local Japanese taxes arising in TokyoThe amounts reported include derivatives used for non-trading purposes other than those designated as formal fair value or net investment accounting hedges. These amounts have not been separately presented since such amounts were not significant as of March 31, 2025 and March 31, 2026.Primarily includes recoveries and foreign exchange movements. The amounts of recoveries for the year ended March 31, 2024 and 2025 and 2026 were not significant.Includes amounts recognized against collateralized agreements, customer contract assets and receivables and other receivables.Includes gains and losses reported primarily within Revenue – Net gain on trading and Revenue—Other in the consolidated statements of income.Includes equity investments that would have been accounted for under the equity method had Nomura not chosen to elect the FVO.Includes unfunded written loan commitments.Includes non-trading debt securities.Includes reverse repurchase and repurchase agreements.Includes structured notes and other financial liabilities.Includes secured financing transactions arising from transfers of financial assets which did not meet the criteria for sales accounting.Includes collateralized loan obligations (“CLOs”) and asset-backed securities (“ABS”) such as those secured on credit card loans, auto loans and student loans.Investments that are carried at fair value using NAV per share as a practical expedient have not been classified in the fair value hierarchy. As of March 31, 2025 and March 31, 2026, the fair values of these investments which are included in Trading assets and private equity and debt investments were ¥73 billion and ¥104 billion, respectively. As of March 31, 2025 and March 31, 2026, the fair values of these investments which are included in Other assets were ¥3 billion and ¥15 billion, respectively.Includes equity investments which comprise listed and unlisted equity securities held for operating purposes in the amounts of ¥72,184 million and ¥26,217 million, respectively, as of March 31, 2025 and ¥97,173 million and ¥26,018 million, respectively, as of March 31, 2026.Private equity and debt investments include minority private equity and venture capital equity investments and other junior debt investments such as mezzanine debt held for non-trading purposes, and post-IPO investments. These investments also include equity investments that would have been accounted for under the equity method had Nomura not chosen to elect the FVO.Includes Japan Securities Clearing Corporation’s clearing fund.Amounts are presented on a gross basis, before the application of counterparty offsetting and are reported within Trading liabilities in the consolidated balance sheets as of March 31, 2025 and March 31, 2026. Of these gross derivative liability amounts, ¥19,401 million and ¥14,221 million are included in interest rate contracts used for trading purposes as of March 31, 2025 and March 31, 2026 respectively as disclosed in Note 3 “Derivative instruments and hedging activities.”Includes loans receivable and loan commitments carried at fair value through election of the fair value option.Includes structured notes for which the FVO has been elected.Includes liabilities recognized from secured financing transactions that are accounted for as financings rather than sales. Nomura elected the fair value option for these liabilities.Includes embedded derivatives bifurcated from issued structured notes. Structured notes are adjusted for fair value changes in corresponding embedded derivatives for presentation in the consolidated balance sheetsIncludes collateralized agreements or collateralized financing for which the FVO has been elected.Includes non-trading debt securities for which the FVO has been elected and AFS debt securities.The earliest year in which Nomura remains subject to examination for transfer pricing issues is the year ended March 31, 2019.The earliest year in which Nomura remains subject to examination for transfer pricing issues is the year ended March 31, 2016.Includes trading balances of secured borrowings.Includes equity securities held for other than trading or operating purposes. These investments comprise listed equity securities and unlisted equity securities of ¥5,889 million and ¥297,085 million respectively, as of March 31, 2025, and ¥15,776 million and ¥370,642 million respectively, as of March 31, 2026. These securities are generally carried at fair value, with changes in fair value recognized and reported within Revenue—Other in the consolidated statements of income. Also includes equity securities without a readily determinable fair value. See Note 6 “Non-trading investments” for further information.Includes a liability of ¥14,240 million and ¥13,077 million as of March 31, 2025 and 2026, respectively, in respect of all outstanding and unsettled investigations, lawsuits and other legal proceedings where loss is considered probable and the amount of such loss can be reasonably estimated. See Note 22 “Commitments, contingencies and guarantees” for further information.Includes embedded derivatives bifurcated from deposits received at banks. Deposits are adjusted for fair value changes in corresponding embedded derivatives for presentation in the consolidated balance sheets.Includes deposits received at banks for which the FVO has been elected.Includes loan commitments for which the FVO has been elected.Includes loans and receivables for which the fair value option has been elected.The earliest year in which Nomura remains subject to examination for transfer pricing issues is the year ended March 31, 2008.A provision for credit losses in connection with settlement failures with a broker counterparty was recognized during the year ended March 31, 2024.Includes operating lease liabilities of ¥20,664 million and ¥19,547 million as of March 31, 2025 and 2026, respectively.Includes ROU assets of ¥20,664 million and ¥19,547 million as of March 31, 2025 and 2026, respectively.The revenue amount does not include revenue of ¥ 56,144 million from the sale in April 2025 by Nomura of its own land and buildings located in Takanawa 2-chome, Minato-ku, Tokyo. The transaction counterparties included Nomura Real Estate Development Co., Ltd., a subsidiary of Nomura Real Estate Holdings, Inc., an affiliated company, and a third-party financing company. Nomura considers the entire transaction to be with a related party. The revenue is included in Revenue—Other in the consolidated statements of income for the year ended March 31, 2026.The revenue amount does not include the dividends from and the movement in fair values of the affiliate investee for which FVO was elected. The revenue is included in Revenue-Interest and dividends and Revenue-Other, respectively in the consolidated statements of income. 0001163653 2025-04-01 2026-03-31 0001163653 2025-03-31 0001163653 2026-03-31 0001163653 2024-04-01 2025-03-31 0001163653 2023-04-01 2024-03-31 0001163653 2024-03-31 0001163653 2025-12-01 0001163653 2023-03-31 0001163653 nmr:UnlistedEquityMember 2025-03-31 0001163653 nmr:ListedEquityMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:DesignatedAsHedgingInstrumentMember 2025-03-31 0001163653 us-gaap:NondesignatedMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:NondesignatedMember 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:NondesignatedMember 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NondesignatedMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:NondesignatedMember 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:NondesignatedMember 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:DesignatedAsHedgingInstrumentMember 2025-03-31 0001163653 us-gaap:DesignatedAsHedgingInstrumentMember 2025-03-31 0001163653 nmr:OtherAssetMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 us-gaap:LoansReceivableMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 us-gaap:CommitmentsToExtendCreditMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 us-gaap:DebtSecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2025-03-31 0001163653 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2025-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:CollateralizedDebtObligationsMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:TransferredToSPEsMember 2025-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2025-03-31 0001163653 us-gaap:ExternalCreditRatingInvestmentGradeMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember 2025-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2025-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2025-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:ExternalCreditRatingInvestmentGradeMember 2025-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:ExternalCreditRatingInvestmentGradeMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:ExternalCreditRatingInvestmentGradeMember 2025-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember nmr:CounterpartyCashCollateralNettingMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember nmr:CounterpartyCashCollateralNettingMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:EquitySecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:OverTheCounterMember 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:ExchangeTradedMember 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:OverTheCounterMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:ExchangeClearedMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:OverTheCounterMember 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:ExchangeTradedMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:ExchangeTradedMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:ExchangeClearedMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:ExchangeTradedMember 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:OverTheCounterMember 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:OverTheCounterMember 2025-03-31 0001163653 nmr:FairValueConcentrationCreditRiskGeographicalOtherCountriesMember nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2025-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2025-03-31 0001163653 country:JP nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2025-03-31 0001163653 country:US nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2025-03-31 0001163653 us-gaap:EuropeanUnionMember nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2025-03-31 0001163653 us-gaap:ShortTermDebtMember 2025-03-31 0001163653 nmr:DerivativeContractsMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember 2025-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember 2025-03-31 0001163653 nmr:EquitiesAndConvertibleBondsMember 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember 2025-03-31 0001163653 nmr:GovernmentAndGovernmentAgencySecuritiesMember 2025-03-31 0001163653 us-gaap:AirTransportationEquipmentMember 2025-03-31 0001163653 us-gaap:LandAndBuildingMember 2025-03-31 0001163653 us-gaap:OtherIntangibleAssetsMember 2025-03-31 0001163653 us-gaap:CustomerRelationshipsMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EstimateOfFairValueFairValueDisclosureMember 2025-03-31 0001163653 us-gaap:CarryingReportedAmountFairValueDisclosureMember 2025-03-31 0001163653 nmr:AffiliatedCompaniesAndOtherEquityMethodInvesteesMember 2025-03-31 0001163653 nmr:MaturityGreaterThan1YearMember 2025-03-31 0001163653 us-gaap:MaturityOvernightAndOnDemandMember 2025-03-31 0001163653 us-gaap:MaturityUpTo30DaysMember 2025-03-31 0001163653 us-gaap:Maturity30To90DaysMember 2025-03-31 0001163653 nmr:Maturity90DaysTo1YearMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NetAssetValueValuationTechniqueMember 2025-03-31 0001163653 nmr:UnsecuredLoansAtBanksMember nmr:CCDMember 2025-03-31 0001163653 nmr:SecuredLoansAtBanksMember nmr:BBCCCMember 2025-03-31 0001163653 nmr:SecuredLoansAtBanksMember nmr:CCDMember 2025-03-31 0001163653 nmr:OthersMember nmr:SecuredLoansAtBanksMember 2025-03-31 0001163653 nmr:CCDMember nmr:UnsecuredCorporateLoansMember 2025-03-31 0001163653 nmr:AdvancesToAffiliatedCompaniesMember nmr:BBCCCMember 2025-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember nmr:BBCCCMember 2025-03-31 0001163653 nmr:AAABBBMember nmr:UnsecuredLoansAtBanksMember 2025-03-31 0001163653 nmr:BBCCCMember nmr:UnsecuredLoansAtBanksMember 2025-03-31 0001163653 nmr:InternallyAssignedGradeTotalMember nmr:UnsecuredLoansAtBanksMember 2025-03-31 0001163653 nmr:InternallyAssignedGradeTotalMember nmr:AdvancesToAffiliatedCompaniesMember 2025-03-31 0001163653 nmr:AdvancesToAffiliatedCompaniesMember nmr:AAABBBMember 2025-03-31 0001163653 nmr:SecuredCorporateLoansMember nmr:BBCCCMember 2025-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember nmr:AAABBBMember 2025-03-31 0001163653 nmr:OthersMember nmr:UnsecuredLoansAtBanksMember 2025-03-31 0001163653 nmr:AdvancesToAffiliatedCompaniesMember nmr:CCDMember 2025-03-31 0001163653 nmr:OthersMember nmr:UnsecuredCorporateLoansMember 2025-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember nmr:CCDMember 2025-03-31 0001163653 nmr:OthersMember nmr:ShortTermSecuredMarginLoansMember 2025-03-31 0001163653 nmr:InternallyAssignedGradeTotalMember nmr:ShortTermSecuredMarginLoansMember 2025-03-31 0001163653 nmr:AAABBBMember nmr:SecuredCorporateLoansMember 2025-03-31 0001163653 nmr:UnsecuredCorporateLoansMember nmr:InternallyAssignedGradeTotalMember 2025-03-31 0001163653 nmr:AdvancesToAffiliatedCompaniesMember nmr:OthersMember 2025-03-31 0001163653 nmr:SecuredLoansAtBanksMember nmr:AAABBBMember 2025-03-31 0001163653 nmr:SecuredLoansAtBanksMember nmr:InternallyAssignedGradeTotalMember 2025-03-31 0001163653 nmr:CCDMember nmr:SecuredCorporateLoansMember 2025-03-31 0001163653 nmr:UnsecuredCorporateLoansMember nmr:BBCCCMember 2025-03-31 0001163653 nmr:SecuredCorporateLoansMember nmr:InternallyAssignedGradeTotalMember 2025-03-31 0001163653 nmr:UnsecuredCorporateLoansMember nmr:AAABBBMember 2025-03-31 0001163653 nmr:OthersMember nmr:SecuredCorporateLoansMember 2025-03-31 0001163653 nmr:FixedRateObligationsMember nmr:NonJapaneseYenDenominatedMember 2025-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember nmr:NonJapaneseYenDenominatedMember 2025-03-31 0001163653 nmr:FloatingRateObligationsMember nmr:JapaneseYenDenominatedMember 2025-03-31 0001163653 nmr:FloatingRateObligationsMember nmr:NonJapaneseYenDenominatedMember 2025-03-31 0001163653 nmr:FixedRateObligationsMember nmr:JapaneseYenDenominatedMember 2025-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember nmr:JapaneseYenDenominatedMember 2025-03-31 0001163653 us-gaap:FinancialStandbyLetterOfCreditMember 2025-03-31 0001163653 us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember nmr:InvestmentTrustFundsAndOtherMember 2025-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueMeasurementsRecurringMember nmr:NetAssetValueValuationTechniqueMember 2025-03-31 0001163653 us-gaap:VentureCapitalFundsMember 2025-03-31 0001163653 us-gaap:RealEstateFundsMember 2025-03-31 0001163653 us-gaap:HedgeFundsMember 2025-03-31 0001163653 nmr:PrivateEquityFundsAndPrivateCreditFundsMember 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:EquityContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CreditRiskContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:InterestRateContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:ForeignExchangeContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:OtherContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDefaultRateMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CommercialMortgageBackedSecuritiesMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CommercialMortgageBackedSecuritiesMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:ResidentialMortgageBackedSecuritiesMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:ResidentialMortgageBackedSecuritiesMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:ResidentialMortgageBackedSecuritiesMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember nmr:RealEstateBackedSecuritiesMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CommercialMortgageBackedSecuritiesMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember nmr:RealEstateBackedSecuritiesMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:ResidentialMortgageBackedSecuritiesMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:ResidentialMortgageBackedSecuritiesMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:ResidentialMortgageBackedSecuritiesMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDefaultRateMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:CollateralizedDebtObligationsMember 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CollateralizedDebtObligationsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember nmr:RealEstateBackedSecuritiesMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:InvestmentTrustFundsAndOtherMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:InvestmentTrustFundsAndOtherMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:CollateralizedDebtObligationsMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:CollateralizedDebtObligationsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:WeightedAverageMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:EquitySecuritiesMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:MaximumMember 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember 2025-03-31 0001163653 srt:MinimumMember nmr:FixedRateObligationsMember 2025-03-31 0001163653 srt:MaximumMember nmr:IndexOrEquityLinkedObligationsMember 2025-03-31 0001163653 srt:MinimumMember nmr:IndexOrEquityLinkedObligationsMember 2025-03-31 0001163653 srt:MaximumMember nmr:FloatingRateObligationsMember 2025-03-31 0001163653 srt:MinimumMember nmr:FloatingRateObligationsMember 2025-03-31 0001163653 srt:MaximumMember nmr:FixedRateObligationsMember 2025-03-31 0001163653 nmr:OverseasSubsidiariesMember 2025-03-31 0001163653 srt:EuropeMember 2025-03-31 0001163653 srt:AmericasMember 2025-03-31 0001163653 country:JP 2025-03-31 0001163653 srt:AsiaPacificMember 2025-03-31 0001163653 nmr:SubtotalMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:AssetPledgedAsCollateralMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRepoRateMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRepoRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:EquityInvestmentsMember nmr:NomuraRealEstateHoldingsIncMember 2025-03-31 0001163653 nmr:EquityInvestmentsMember nmr:NomuraResearchInstituteLtdMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel1Member nmr:NonJapanPlanMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:NonJapanPlanMember 2025-03-31 0001163653 nmr:NonJapanPlanMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel2Member nmr:NonJapanPlanMember 2025-03-31 0001163653 nmr:NomuraRealEstateHoldingsIncMember 2025-03-31 0001163653 nmr:NomuraSecuritiesMember 2025-03-31 0001163653 nmr:NomuraFinancialProductsAndServicesIncMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:AmericanCenturyCompaniesIncMember 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember 2025-03-31 0001163653 nmr:MaintenanceAgreementsMember nmr:OtherCommitmentsMember 2025-03-31 0001163653 srt:AffiliatedEntityMember 2025-03-31 0001163653 nmr:LoansAtBanksMember 2025-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember 2025-03-31 0001163653 us-gaap:CommercialPortfolioSegmentMember 2025-03-31 0001163653 srt:ParentCompanyMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel12And3Member 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:PrivateEquityAndPooledInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 nmr:PrivateEquityAndPooledInvestmentsMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel12And3Member 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel12And3Member 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 nmr:PrivateEquityAndPooledInvestmentsMember us-gaap:FairValueInputsLevel12And3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel2Member nmr:PrivateEquityAndPooledInvestmentsMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel12And3Member 2025-03-31 0001163653 nmr:LifeInsuranceCompanyGeneralAccountsMember us-gaap:FairValueInputsLevel1Member 2025-03-31 0001163653 nmr:LifeInsuranceCompanyGeneralAccountsMember us-gaap:FairValueInputsLevel2Member 2025-03-31 0001163653 nmr:LifeInsuranceCompanyGeneralAccountsMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:LifeInsuranceCompanyGeneralAccountsMember us-gaap:FairValueInputsLevel12And3Member 2025-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember 2025-03-31 0001163653 nmr:InvestmentsInAndAdvancesToAffiliatedCompaniesMember 2025-03-31 0001163653 us-gaap:PropertyPlantAndEquipmentMember 2025-03-31 0001163653 us-gaap:LoansReceivableMember 2025-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember 2025-03-31 0001163653 nmr:TradingAssetsAndPrivateEquityAndDebtInvestmentsMember 2025-03-31 0001163653 nmr:BondsAndNotesIssuedMember 2025-03-31 0001163653 nmr:LongTermBorrowingsFromBanksAndFinancialInstitutionsMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember 2025-03-31 0001163653 nmr:AffiliateGroupMember 2025-03-31 0001163653 nmr:OtcDerivativesWithFinancialInstitutionsMember 2025-03-31 0001163653 nmr:OtherCommitmentsMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2025-03-31 0001163653 nmr:NotLaterThanOneYearMember 2025-03-31 0001163653 nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2025-03-31 0001163653 nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2025-03-31 0001163653 nmr:LaterThanFiveYearsMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:LaterThanFiveYearsMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:NotLaterThanOneYearMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:LaterThanFiveYearsMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:LaterThanFiveYearsMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:NotLaterThanOneYearMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:NotLaterThanOneYearMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:NotLaterThanOneYearMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:LaterThanFiveYearsMember 2025-03-31 0001163653 nmr:OtherCommitmentsToExtendCreditMember 2025-03-31 0001163653 nmr:LiquidityFacilitiesToCentralClearingCounterpartiesMember 2025-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2025-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember 2025-03-31 0001163653 nmr:FloatingRateObligationsMember 2025-03-31 0001163653 nmr:FixedRateObligationsMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MinimumMember 2025-03-31 0001163653 srt:StandardPoorsAARatingMember 2025-03-31 0001163653 srt:StandardPoorsARatingMember 2025-03-31 0001163653 srt:StandardPoorsBBBRatingMember 2025-03-31 0001163653 srt:StandardPoorsBBRatingMember 2025-03-31 0001163653 nmr:StandardPoorSOtherRatingMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:StandardPoorSOtherRatingMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsBBBRatingMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:StandardPoorSOtherRatingMember 2025-03-31 0001163653 srt:StandardPoorsAAARatingMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsBBRatingMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:StandardPoorSOtherRatingMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsARatingMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsBBBRatingMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsBBRatingMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:StandardPoorSOtherRatingMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsAAARatingMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsAARatingMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsARatingMember 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsBBBRatingMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsAAARatingMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsAARatingMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsARatingMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsBBBRatingMember 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsBBRatingMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsBBRatingMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsARatingMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsAARatingMember 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsAAARatingMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsAARatingMember 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsAAARatingMember 2025-03-31 0001163653 nmr:CSUsMember 2025-03-31 0001163653 nmr:NSUsMember 2025-03-31 0001163653 us-gaap:LongTermDebtMember 2025-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2025-03-31 0001163653 us-gaap:AccountingStandardsUpdate201602Member 2025-03-31 0001163653 us-gaap:OtherLiabilitiesMember 2025-03-31 0001163653 nmr:UnlistedEquityMember 2025-03-31 0001163653 nmr:ListedEquityMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MaximumMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:WeightedAverageMember 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2025-03-31 0001163653 nmr:EquipmentAndFacilitiesMember 2025-03-31 0001163653 us-gaap:BuildingMember 2025-03-31 0001163653 us-gaap:ComputerEquipmentMember 2025-03-31 0001163653 us-gaap:LandMember 2025-03-31 0001163653 us-gaap:ConstructionInProgressMember 2025-03-31 0001163653 us-gaap:SaleAndTotalReturnSwapMember 2025-03-31 0001163653 us-gaap:InterestRateContractMember 2025-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember 2025-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember 2025-03-31 0001163653 nmr:LaterThanOneYearAndNotLaterThanFiveYearsMember 2025-03-31 0001163653 nmr:NonBdEntitiesOtherThanInvestmentCompaniesMember 2025-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraInternationalFundingPteLtdMember 2025-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraEuropeFinanceNVMember 2025-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraInternationalplcMember 2025-03-31 0001163653 srt:ParentCompanyMember nmr:DerivativeGuaranteeMember nmr:NomuraInternationalplcMember 2025-03-31 0001163653 srt:ParentCompanyMember nmr:DerivativeGuaranteeMember nmr:NomuraGlobalFinancialProductsIncMember 2025-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraBankInternationalplcMember 2025-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraGlobalFinanceCoLtdMember 2025-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraCorporateFundingAmericansLLCMember 2025-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraAmericaFinanceLLCMember 2025-03-31 0001163653 srt:ParentCompanyMember nmr:OthersMember 2025-03-31 0001163653 nmr:UnlistedEquityMember 2026-03-31 0001163653 nmr:ListedEquityMember 2026-03-31 0001163653 us-gaap:NondesignatedMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:NondesignatedMember 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:NondesignatedMember 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NondesignatedMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:NondesignatedMember 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:NondesignatedMember 2026-03-31 0001163653 us-gaap:DesignatedAsHedgingInstrumentMember 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:DesignatedAsHedgingInstrumentMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:DesignatedAsHedgingInstrumentMember 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:LoansReceivableMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 nmr:OtherAssetMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:CommitmentsToExtendCreditMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:DebtSecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember 2026-03-31 0001163653 nmr:TransferredToSPEsMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:ExternalCreditRatingInvestmentGradeMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2026-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2026-03-31 0001163653 us-gaap:ExternalCreditRatingInvestmentGradeMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember 2026-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:ExternalCreditRatingNonInvestmentGradeMember 2026-03-31 0001163653 us-gaap:MortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember us-gaap:ExternalCreditRatingInvestmentGradeMember 2026-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember nmr:CounterpartyCashCollateralNettingMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:EquitySecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember nmr:CounterpartyCashCollateralNettingMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:IssuedGuaranteedByGovernmentSponsoredEntityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherResidentialMortgagebackedSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:ExchangeTradedMember 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:ExchangeTradedMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:OverTheCounterMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:ExchangeTradedMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:OverTheCounterMember 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:OverTheCounterMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:ExchangeClearedMember 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:OverTheCounterMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:ExchangeClearedMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:ExchangeTradedMember 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:OverTheCounterMember 2026-03-31 0001163653 country:US nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2026-03-31 0001163653 nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2026-03-31 0001163653 country:JP nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2026-03-31 0001163653 nmr:FairValueConcentrationCreditRiskGeographicalOtherCountriesMember nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2026-03-31 0001163653 us-gaap:EuropeanUnionMember nmr:GovernmentAgencyAndMunicipalSecuritiesMember 2026-03-31 0001163653 us-gaap:ShortTermDebtMember 2026-03-31 0001163653 nmr:DerivativeContractsMember 2026-03-31 0001163653 us-gaap:FinancialStandbyLetterOfCreditMember 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember 2026-03-31 0001163653 nmr:EquitiesAndConvertibleBondsMember 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember 2026-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember 2026-03-31 0001163653 nmr:GovernmentAndGovernmentAgencySecuritiesMember 2026-03-31 0001163653 us-gaap:AirTransportationEquipmentMember 2026-03-31 0001163653 us-gaap:LandAndBuildingMember 2026-03-31 0001163653 us-gaap:OtherIntangibleAssetsMember 2026-03-31 0001163653 us-gaap:CustomerRelationshipsMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CarryingReportedAmountFairValueDisclosureMember 2026-03-31 0001163653 us-gaap:EstimateOfFairValueFairValueDisclosureMember 2026-03-31 0001163653 nmr:AffiliatedCompaniesAndOtherEquityMethodInvesteesMember 2026-03-31 0001163653 us-gaap:MaturityOvernightAndOnDemandMember 2026-03-31 0001163653 us-gaap:MaturityUpTo30DaysMember 2026-03-31 0001163653 us-gaap:Maturity30To90DaysMember 2026-03-31 0001163653 nmr:Maturity90DaysTo1YearMember 2026-03-31 0001163653 nmr:MaturityGreaterThan1YearMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NetAssetValueValuationTechniqueMember 2026-03-31 0001163653 nmr:OtherCommitmentsMember 2026-03-31 0001163653 nmr:BBCCCMember nmr:ShortTermSecuredMarginLoansMember 2026-03-31 0001163653 nmr:SecuredLoansAtBanksMember nmr:InternallyAssignedGradeTotalMember 2026-03-31 0001163653 nmr:SecuredCorporateLoansMember nmr:InternallyAssignedGradeTotalMember 2026-03-31 0001163653 nmr:AAABBBMember nmr:AdvancesToAffiliatedCompaniesMember 2026-03-31 0001163653 nmr:OthersMember nmr:AdvancesToAffiliatedCompaniesMember 2026-03-31 0001163653 nmr:SecuredCorporateLoansMember nmr:AAABBBMember 2026-03-31 0001163653 nmr:AdvancesToAffiliatedCompaniesMember nmr:InternallyAssignedGradeTotalMember 2026-03-31 0001163653 nmr:AdvancesToAffiliatedCompaniesMember nmr:CCDMember 2026-03-31 0001163653 nmr:UnsecuredCorporateLoansMember nmr:CCDMember 2026-03-31 0001163653 nmr:UnsecuredCorporateLoansMember nmr:AAABBBMember 2026-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember nmr:OthersMember 2026-03-31 0001163653 nmr:CCDMember nmr:SecuredLoansAtBanksMember 2026-03-31 0001163653 nmr:BBCCCMember nmr:SecuredLoansAtBanksMember 2026-03-31 0001163653 nmr:SecuredLoansAtBanksMember nmr:AAABBBMember 2026-03-31 0001163653 nmr:SecuredCorporateLoansMember nmr:OthersMember 2026-03-31 0001163653 nmr:SecuredCorporateLoansMember nmr:CCDMember 2026-03-31 0001163653 nmr:BBCCCMember nmr:SecuredCorporateLoansMember 2026-03-31 0001163653 nmr:OthersMember nmr:UnsecuredCorporateLoansMember 2026-03-31 0001163653 nmr:UnsecuredLoansAtBanksMember nmr:InternallyAssignedGradeTotalMember 2026-03-31 0001163653 nmr:UnsecuredLoansAtBanksMember nmr:OthersMember 2026-03-31 0001163653 nmr:CCDMember nmr:UnsecuredLoansAtBanksMember 2026-03-31 0001163653 nmr:BBCCCMember nmr:UnsecuredLoansAtBanksMember 2026-03-31 0001163653 nmr:OthersMember nmr:SecuredLoansAtBanksMember 2026-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember nmr:InternallyAssignedGradeTotalMember 2026-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember nmr:CCDMember 2026-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember nmr:AAABBBMember 2026-03-31 0001163653 nmr:UnsecuredLoansAtBanksMember nmr:AAABBBMember 2026-03-31 0001163653 nmr:AdvancesToAffiliatedCompaniesMember nmr:BBCCCMember 2026-03-31 0001163653 nmr:UnsecuredCorporateLoansMember nmr:InternallyAssignedGradeTotalMember 2026-03-31 0001163653 nmr:UnsecuredCorporateLoansMember nmr:BBCCCMember 2026-03-31 0001163653 nmr:FixedRateObligationsMember nmr:NonJapaneseYenDenominatedMember 2026-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember nmr:JapaneseYenDenominatedMember 2026-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember nmr:NonJapaneseYenDenominatedMember 2026-03-31 0001163653 nmr:FixedRateObligationsMember nmr:JapaneseYenDenominatedMember 2026-03-31 0001163653 nmr:FloatingRateObligationsMember nmr:JapaneseYenDenominatedMember 2026-03-31 0001163653 nmr:FloatingRateObligationsMember nmr:NonJapaneseYenDenominatedMember 2026-03-31 0001163653 nmr:NotLaterThanOneYearMember us-gaap:FinancialStandbyLetterOfCreditMember 2026-03-31 0001163653 nmr:NotLaterThanOneYearMember nmr:DerivativeContractsMember 2026-03-31 0001163653 nmr:LaterThanOneYearNotLaterThanThreeYearsMember nmr:DerivativeContractsMember 2026-03-31 0001163653 nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember nmr:DerivativeContractsMember 2026-03-31 0001163653 nmr:LaterThanFiveYearsMember nmr:DerivativeContractsMember 2026-03-31 0001163653 nmr:LaterThanOneYearNotLaterThanThreeYearsMember us-gaap:FinancialStandbyLetterOfCreditMember 2026-03-31 0001163653 nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember us-gaap:FinancialStandbyLetterOfCreditMember 2026-03-31 0001163653 nmr:LaterThanFiveYearsMember us-gaap:FinancialStandbyLetterOfCreditMember 2026-03-31 0001163653 us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember nmr:InvestmentTrustFundsAndOtherMember 2026-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueMeasurementsRecurringMember nmr:NetAssetValueValuationTechniqueMember 2026-03-31 0001163653 us-gaap:HedgeFundsMember 2026-03-31 0001163653 nmr:PrivateEquityFundsAndPrivateCreditFundsMember 2026-03-31 0001163653 us-gaap:VentureCapitalFundsMember 2026-03-31 0001163653 us-gaap:RealEstateFundsMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:EquityContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:InterestRateContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:CreditRiskContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:ForeignExchangeContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember us-gaap:OtherContractMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember nmr:RealEstateBackedSecuritiesMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:InvestmentTrustFundsAndOtherMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDefaultRateMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CollateralizedDebtObligationsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CollateralizedDebtObligationsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:CollateralizedDebtObligationsMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:InvestmentTrustFundsAndOtherMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:ResidentialMortgageBackedSecuritiesMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember nmr:RealEstateBackedSecuritiesMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CollateralizedDebtObligationsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CollateralizedDebtObligationsMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDefaultRateMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CollateralizedDebtObligationsMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember nmr:PrivateEquityAndDebtInvestmentsMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:ForeignGovernmentDebtSecuritiesMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 srt:MaximumMember nmr:IndexOrEquityLinkedObligationsMember 2026-03-31 0001163653 srt:MinimumMember nmr:IndexOrEquityLinkedObligationsMember 2026-03-31 0001163653 srt:MaximumMember nmr:FloatingRateObligationsMember 2026-03-31 0001163653 srt:MinimumMember nmr:FloatingRateObligationsMember 2026-03-31 0001163653 srt:MaximumMember nmr:FixedRateObligationsMember 2026-03-31 0001163653 srt:MinimumMember nmr:FixedRateObligationsMember 2026-03-31 0001163653 nmr:OverseasSubsidiariesMember 2026-03-31 0001163653 srt:AmericasMember 2026-03-31 0001163653 nmr:SubtotalMember 2026-03-31 0001163653 country:JP 2026-03-31 0001163653 srt:EuropeMember 2026-03-31 0001163653 srt:AsiaPacificMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:AssetPledgedAsCollateralMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember 2026-03-31 0001163653 srt:MinimumMember nmr:EquityInvestmentsMember 2026-03-31 0001163653 srt:MaximumMember nmr:EquityInvestmentsMember 2026-03-31 0001163653 srt:MinimumMember nmr:LimitedPartnershipMember nmr:EquityInvestmentsMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRepoRateMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRepoRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRepoRateMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:LifeInsuranceCompanyGeneralAccountsMember 2026-03-31 0001163653 nmr:OtherPensionPlanAssetsMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember 2026-03-31 0001163653 us-gaap:DebtSecuritiesMember 2026-03-31 0001163653 nmr:EquityInvestmentsMember nmr:NomuraResearchInstituteLtdMember 2026-03-31 0001163653 nmr:EquityInvestmentsMember nmr:NomuraRealEstateHoldingsIncMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:NonJapanPlanMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:NonJapanPlanMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel1Member nmr:NonJapanPlanMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel2Member nmr:NonJapanPlanMember 2026-03-31 0001163653 nmr:NomuraRealEstateHoldingsIncMember 2026-03-31 0001163653 nmr:NomuraFinancialProductsAndServicesIncMember 2026-03-31 0001163653 nmr:NomuraSecuritiesMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember 2026-03-31 0001163653 nmr:AmericanCenturyCompaniesIncMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember 2026-03-31 0001163653 nmr:InstinetLLCMember 2026-03-31 0001163653 nmr:NomuraSecuritiesInternationalIncMember 2026-03-31 0001163653 nmr:NomuraGlobalFinancialProductsIncMember 2026-03-31 0001163653 nmr:MaintenanceAgreementsMember nmr:OtherCommitmentsMember 2026-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember 2026-03-31 0001163653 nmr:LoansAtBanksMember 2026-03-31 0001163653 srt:AffiliatedEntityMember 2026-03-31 0001163653 srt:ParentCompanyMember 2026-03-31 0001163653 us-gaap:CommercialPortfolioSegmentMember 2026-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 nmr:PrivateEquityAndPooledInvestmentsMember us-gaap:FairValueInputsLevel12And3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:JapaneseGovernmentDebtSecuritiesMember 2026-03-31 0001163653 nmr:PrivateEquityAndPooledInvestmentsMember us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel12And3Member 2026-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel12And3Member 2026-03-31 0001163653 nmr:LifeInsuranceCompanyGeneralAccountsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:LifeInsuranceCompanyGeneralAccountsMember us-gaap:FairValueInputsLevel12And3Member 2026-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 nmr:OtherPensionPlanAssetsMember us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 nmr:PrivateEquityAndPooledInvestmentsMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:PrivateEquityAndPooledInvestmentsMember us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel1Member 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel2Member 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel12And3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel1Member nmr:LifeInsuranceCompanyGeneralAccountsMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel2Member nmr:LifeInsuranceCompanyGeneralAccountsMember 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel12And3Member 2026-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember 2026-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember 2026-03-31 0001163653 nmr:InvestmentsInAndAdvancesToAffiliatedCompaniesMember 2026-03-31 0001163653 us-gaap:LoansReceivableMember 2026-03-31 0001163653 us-gaap:PropertyPlantAndEquipmentMember 2026-03-31 0001163653 nmr:TradingAssetsAndPrivateEquityAndDebtInvestmentsMember 2026-03-31 0001163653 nmr:BondsAndNotesIssuedMember 2026-03-31 0001163653 nmr:LongTermBorrowingsFromBanksAndFinancialInstitutionsMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember 2026-03-31 0001163653 nmr:AffiliateGroupMember 2026-03-31 0001163653 nmr:OtcDerivativesWithFinancialInstitutionsMember 2026-03-31 0001163653 nmr:NotLaterThanOneYearMember 2026-03-31 0001163653 nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2026-03-31 0001163653 nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2026-03-31 0001163653 nmr:LaterThanFiveYearsMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:NotLaterThanOneYearMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:LaterThanFiveYearsMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:LaterThanFiveYearsMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:LaterThanFiveYearsMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:NotLaterThanOneYearMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:NotLaterThanOneYearMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:NotLaterThanOneYearMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:LaterThanOneYearNotLaterThanThreeYearsMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:LaterThanFiveYearsMember 2026-03-31 0001163653 nmr:OtherCommitmentsToExtendCreditMember 2026-03-31 0001163653 nmr:LiquidityFacilitiesToCentralClearingCounterpartiesMember 2026-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2026-03-31 0001163653 nmr:FloatingRateObligationsMember 2026-03-31 0001163653 nmr:FixedRateObligationsMember 2026-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember 2026-03-31 0001163653 nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember nmr:OtherCommitmentsToExtendCreditMember 2026-03-31 0001163653 nmr:NotLaterThanOneYearMember nmr:LiquidityFacilitiesToCentralClearingCounterpartiesMember 2026-03-31 0001163653 nmr:LaterThanFiveYearsMember nmr:OtherCommitmentsToExtendCreditMember 2026-03-31 0001163653 nmr:LaterThanFiveYearsMember nmr:LiquidityFacilitiesToCentralClearingCounterpartiesMember 2026-03-31 0001163653 nmr:LaterThanThreeYearsNotLaterThanFiveYearsMember nmr:LiquidityFacilitiesToCentralClearingCounterpartiesMember 2026-03-31 0001163653 nmr:LaterThanOneYearNotLaterThanThreeYearsMember nmr:LiquidityFacilitiesToCentralClearingCounterpartiesMember 2026-03-31 0001163653 nmr:LaterThanOneYearNotLaterThanThreeYearsMember nmr:OtherCommitmentsToExtendCreditMember 2026-03-31 0001163653 nmr:NotLaterThanOneYearMember nmr:OtherCommitmentsToExtendCreditMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember 2026-03-31 0001163653 nmr:NSUsMember 2026-03-31 0001163653 nmr:CSUsMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsAAARatingMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsAARatingMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsARatingMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsBBBRatingMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember srt:StandardPoorsBBRatingMember 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember nmr:StandardPoorSOtherRatingMember 2026-03-31 0001163653 srt:StandardPoorsAAARatingMember 2026-03-31 0001163653 srt:StandardPoorsAARatingMember 2026-03-31 0001163653 srt:StandardPoorsARatingMember 2026-03-31 0001163653 srt:StandardPoorsBBBRatingMember 2026-03-31 0001163653 srt:StandardPoorsBBRatingMember 2026-03-31 0001163653 nmr:StandardPoorSOtherRatingMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsAARatingMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsARatingMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsBBRatingMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember nmr:StandardPoorSOtherRatingMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsAARatingMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsARatingMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsBBBRatingMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsBBRatingMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember nmr:StandardPoorSOtherRatingMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsAAARatingMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsAARatingMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsARatingMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsBBBRatingMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember srt:StandardPoorsBBRatingMember 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember nmr:StandardPoorSOtherRatingMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsBBBRatingMember 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember srt:StandardPoorsAAARatingMember 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember srt:StandardPoorsAAARatingMember 2026-03-31 0001163653 us-gaap:LongTermDebtMember 2026-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:OtherAssetsAggregateCarryingAmountsMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:CounterpartyCashCollateralNettingMember nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 nmr:NonTradingDebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2026-03-31 0001163653 us-gaap:AccountingStandardsUpdate201602Member 2026-03-31 0001163653 srt:SubsidiariesMember us-gaap:HerMajestysRevenueAndCustomsHMRCMember 2026-03-31 0001163653 nmr:NomuraHoldingsIncMember us-gaap:NationalTaxAgencyJapanMember 2026-03-31 0001163653 nmr:TwoThousandTwentyThreeAndThereafterExpirationPeriodMember 2026-03-31 0001163653 nmr:TwoThousandThirteenThroughTwoThousandTwentyTwoExpirationPeriodMember 2026-03-31 0001163653 nmr:OperatingLossCarryforwardsIndefinitelyMember 2026-03-31 0001163653 srt:SubsidiariesMember us-gaap:ForeignCountryMember 2026-03-31 0001163653 srt:SubsidiariesMember us-gaap:InlandRevenueHongKongMember 2026-03-31 0001163653 srt:SubsidiariesMember us-gaap:InternalRevenueServiceIRSMember 2026-03-31 0001163653 us-gaap:OtherLiabilitiesMember 2026-03-31 0001163653 nmr:UnlistedEquityMember 2026-03-31 0001163653 nmr:ListedEquityMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:WeightedAverageMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:MaximumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MinimumMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember srt:WeightedAverageMember us-gaap:FairValueInputsLevel3Member 2026-03-31 0001163653 us-gaap:ComputerEquipmentMember 2026-03-31 0001163653 nmr:EquipmentAndFacilitiesMember 2026-03-31 0001163653 us-gaap:LandMember 2026-03-31 0001163653 us-gaap:ConstructionInProgressMember 2026-03-31 0001163653 us-gaap:BuildingMember 2026-03-31 0001163653 us-gaap:SaleAndTotalReturnSwapMember 2026-03-31 0001163653 us-gaap:InterestRateContractMember 2026-03-31 0001163653 us-gaap:ComputerSoftwareIntangibleAssetMember srt:MaximumMember 2026-03-31 0001163653 us-gaap:ComputerSoftwareIntangibleAssetMember srt:MinimumMember 2026-03-31 0001163653 srt:MaximumMember nmr:EquipmentAndFacilitiesMember 2026-03-31 0001163653 srt:MinimumMember nmr:EquipmentAndFacilitiesMember 2026-03-31 0001163653 srt:MaximumMember us-gaap:BuildingMember 2026-03-31 0001163653 srt:MinimumMember us-gaap:BuildingMember 2026-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember 2026-03-31 0001163653 nmr:JapaneseGovernmentDebtSecuritiesMember 2026-03-31 0001163653 nmr:LaterThanOneYearAndNotLaterThanFiveYearsMember 2026-03-31 0001163653 us-gaap:GeographicDistributionForeignMember 2026-03-31 0001163653 us-gaap:GeographicDistributionDomesticMember 2026-03-31 0001163653 us-gaap:GeographicDistributionForeignMember us-gaap:BankTimeDepositsMember 2026-03-31 0001163653 us-gaap:GeographicDistributionForeignMember us-gaap:CertificatesOfDepositMember 2026-03-31 0001163653 us-gaap:GeographicDistributionDomesticMember us-gaap:CertificatesOfDepositMember 2026-03-31 0001163653 us-gaap:GeographicDistributionDomesticMember us-gaap:BankTimeDepositsMember 2026-03-31 0001163653 us-gaap:CertificatesOfDepositMember 2026-03-31 0001163653 us-gaap:BankTimeDepositsMember 2026-03-31 0001163653 nmr:NonBdEntitiesOtherThanInvestmentCompaniesMember 2026-03-31 0001163653 nmr:MacquarieManagementHoldingsIncMember 2026-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraCorporateFundingAmericansLLCMember 2026-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraBankInternationalplcMember 2026-03-31 0001163653 srt:ParentCompanyMember nmr:DerivativeGuaranteeMember nmr:NomuraGlobalFinancialProductsIncMember 2026-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraAmericaFinanceLLCMember 2026-03-31 0001163653 srt:ParentCompanyMember nmr:OthersMember 2026-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraGlobalFinanceCoLtdMember 2026-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraInternationalFundingPteLtdMember 2026-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraInternationalplcMember 2026-03-31 0001163653 srt:ParentCompanyMember us-gaap:FinancialGuaranteeMember nmr:NomuraEuropeFinanceNVMember 2026-03-31 0001163653 srt:ParentCompanyMember nmr:DerivativeGuaranteeMember nmr:NomuraInternationalplcMember 2026-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2023-04-01 2024-03-31 0001163653 us-gaap:AdditionalPaidInCapitalMember 2023-04-01 2024-03-31 0001163653 country:JP 2023-04-01 2024-03-31 0001163653 srt:AmericasMember 2023-04-01 2024-03-31 0001163653 srt:EuropeMember 2023-04-01 2024-03-31 0001163653 srt:AsiaPacificMember 2023-04-01 2024-03-31 0001163653 nmr:SubtotalMember 2023-04-01 2024-03-31 0001163653 nmr:AllOtherAndEliminationsMember 2023-04-01 2024-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember 2023-04-01 2024-03-31 0001163653 nmr:OtherLiabilitiesMeasuredAtFairValueUsingTheFairValueOptionMember 2023-04-01 2024-03-31 0001163653 us-gaap:LongTermDebtMember 2023-04-01 2024-03-31 0001163653 us-gaap:TradingAssetsExcludingDebtAndEquitySecuritiesMember 2023-04-01 2024-03-31 0001163653 us-gaap:ShortTermDebtMember 2023-04-01 2024-03-31 0001163653 us-gaap:AssetsMember 2023-04-01 2024-03-31 0001163653 nmr:CollateralizedFinancingMember 2023-04-01 2024-03-31 0001163653 us-gaap:LoansReceivableMember 2023-04-01 2024-03-31 0001163653 nmr:PayablesAndDepositsMember 2023-04-01 2024-03-31 0001163653 nmr:InvestmentsAndOtherAssetsOtherMember 2023-04-01 2024-03-31 0001163653 nmr:CollateralizedAgreementsMember 2023-04-01 2024-03-31 0001163653 us-gaap:LiabilityMember 2023-04-01 2024-03-31 0001163653 us-gaap:EquityMethodInvesteeMember 2023-04-01 2024-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2023-04-01 2024-03-31 0001163653 us-gaap:FairValueHedgingMember 2023-04-01 2024-03-31 0001163653 us-gaap:LongTermDebtMember us-gaap:FairValueHedgingMember 2023-04-01 2024-03-31 0001163653 us-gaap:DesignatedAsHedgingInstrumentMember 2023-04-01 2024-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:DesignatedAsHedgingInstrumentMember 2023-04-01 2024-03-31 0001163653 us-gaap:NetInvestmentHedgingMember 2023-04-01 2024-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NetInvestmentHedgingMember 2023-04-01 2024-03-31 0001163653 us-gaap:EquityContractMember us-gaap:NondesignatedMember 2023-04-01 2024-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:NondesignatedMember 2023-04-01 2024-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:NondesignatedMember 2023-04-01 2024-03-31 0001163653 us-gaap:OtherContractMember us-gaap:NondesignatedMember 2023-04-01 2024-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NondesignatedMember 2023-04-01 2024-03-31 0001163653 us-gaap:NondesignatedMember 2023-04-01 2024-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2023-04-01 2024-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2023-04-01 2024-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember 2023-04-01 2024-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember 2023-04-01 2024-03-31 0001163653 us-gaap:CommercialPortfolioSegmentMember 2023-04-01 2024-03-31 0001163653 nmr:LoansAtBanksMember 2023-04-01 2024-03-31 0001163653 us-gaap:RetainedEarningsMember 2023-04-01 2024-03-31 0001163653 us-gaap:NoncontrollingInterestMember 2023-04-01 2024-03-31 0001163653 us-gaap:TreasuryStockCommonMember 2023-04-01 2024-03-31 0001163653 nmr:WealthManagementSegmentMember 2023-04-01 2024-03-31 0001163653 nmr:InvestmentManagementMember 2023-04-01 2024-03-31 0001163653 nmr:WholesaleSegmentMember 2023-04-01 2024-03-31 0001163653 nmr:BankingSegmentMember 2023-04-01 2024-03-31 0001163653 nmr:AffiliateGroupMember 2023-04-01 2024-03-31 0001163653 nmr:AffiliatedCompaniesAndOtherEquityMethodInvesteesMember 2023-04-01 2024-03-31 0001163653 nmr:NSUsAndCSUsMember 2023-04-01 2024-03-31 0001163653 nmr:RSUandSARMember 2023-04-01 2024-03-31 0001163653 nmr:BrokerageCommissionsMember 2023-04-01 2024-03-31 0001163653 nmr:OtherCommissionsMember 2023-04-01 2024-03-31 0001163653 nmr:CommissionsForDistributionOfInvestmentTrustMember 2023-04-01 2024-03-31 0001163653 nmr:OccupancyAndRelatedDepreciationMember 2023-04-01 2024-03-31 0001163653 nmr:InformationProcessingAndCommunicationsMember 2023-04-01 2024-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2023-04-01 2024-03-31 0001163653 srt:ParentCompanyMember 2023-04-01 2024-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2024-04-01 2025-03-31 0001163653 nmr:FixedRateObligationsMember 2024-04-01 2025-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember 2024-04-01 2025-03-31 0001163653 nmr:FloatingRateObligationsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:OtherContractMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember 2024-04-01 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember 2024-04-01 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:DerivativeMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2024-04-01 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:SubtotalAssetsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:AdditionalPaidInCapitalMember 2024-04-01 2025-03-31 0001163653 srt:AmericasMember 2024-04-01 2025-03-31 0001163653 srt:AsiaPacificMember 2024-04-01 2025-03-31 0001163653 srt:EuropeMember 2024-04-01 2025-03-31 0001163653 country:JP 2024-04-01 2025-03-31 0001163653 nmr:SubtotalMember 2024-04-01 2025-03-31 0001163653 nmr:AllOtherAndEliminationsMember 2024-04-01 2025-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember 2024-04-01 2025-03-31 0001163653 nmr:CollateralizedFinancingMember 2024-04-01 2025-03-31 0001163653 us-gaap:LongTermDebtMember 2024-04-01 2025-03-31 0001163653 us-gaap:TradingAssetsExcludingDebtAndEquitySecuritiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:AssetsMember 2024-04-01 2025-03-31 0001163653 us-gaap:LoansReceivableMember 2024-04-01 2025-03-31 0001163653 nmr:PayablesAndDepositsMember 2024-04-01 2025-03-31 0001163653 us-gaap:ShortTermDebtMember 2024-04-01 2025-03-31 0001163653 nmr:InvestmentsAndOtherAssetsOtherMember 2024-04-01 2025-03-31 0001163653 nmr:CollateralizedAgreementsMember 2024-04-01 2025-03-31 0001163653 nmr:OtherLiabilitiesMeasuredAtFairValueUsingTheFairValueOptionMember 2024-04-01 2025-03-31 0001163653 us-gaap:LiabilityMember 2024-04-01 2025-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2024-04-01 2025-03-31 0001163653 us-gaap:EquityMethodInvesteeMember 2024-04-01 2025-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueHedgingMember 2024-04-01 2025-03-31 0001163653 us-gaap:LongTermDebtMember us-gaap:FairValueHedgingMember 2024-04-01 2025-03-31 0001163653 us-gaap:DesignatedAsHedgingInstrumentMember 2024-04-01 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:DesignatedAsHedgingInstrumentMember 2024-04-01 2025-03-31 0001163653 us-gaap:NetInvestmentHedgingMember 2024-04-01 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NetInvestmentHedgingMember 2024-04-01 2025-03-31 0001163653 us-gaap:NondesignatedMember 2024-04-01 2025-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:NondesignatedMember 2024-04-01 2025-03-31 0001163653 us-gaap:EquityContractMember us-gaap:NondesignatedMember 2024-04-01 2025-03-31 0001163653 us-gaap:OtherContractMember us-gaap:NondesignatedMember 2024-04-01 2025-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NondesignatedMember 2024-04-01 2025-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:NondesignatedMember 2024-04-01 2025-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2024-04-01 2025-03-31 0001163653 us-gaap:AccumulatedNetUnrealizedInvestmentGainLossMember 2024-04-01 2025-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember 2024-04-01 2025-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2024-04-01 2025-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember 2024-04-01 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember 2024-04-01 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-04-01 2025-03-31 0001163653 nmr:LoansAtBanksMember 2024-04-01 2025-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember 2024-04-01 2025-03-31 0001163653 us-gaap:CommercialPortfolioSegmentMember 2024-04-01 2025-03-31 0001163653 us-gaap:RetainedEarningsMember 2024-04-01 2025-03-31 0001163653 nmr:WholesaleSegmentMember 2024-04-01 2025-03-31 0001163653 us-gaap:NoncontrollingInterestMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:NonJapanPlanMember 2024-04-01 2025-03-31 0001163653 us-gaap:TreasuryStockCommonMember 2024-04-01 2025-03-31 0001163653 nmr:OtherCommitmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:PrivateEquityAndPooledInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:InvestmentTrustFundsAndOtherMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 nmr:BankingSegmentMember 2024-04-01 2025-03-31 0001163653 nmr:WealthManagementSegmentMember 2024-04-01 2025-03-31 0001163653 nmr:InvestmentManagementMember 2024-04-01 2025-03-31 0001163653 nmr:PrivateEquityFundsAndPrivateCreditFundsMember 2024-04-01 2025-03-31 0001163653 us-gaap:RealEstateFundsMember 2024-04-01 2025-03-31 0001163653 us-gaap:HedgeFundsMember 2024-04-01 2025-03-31 0001163653 us-gaap:VentureCapitalFundsMember 2024-04-01 2025-03-31 0001163653 srt:MinimumMember us-gaap:HedgeFundsMember 2024-04-01 2025-03-31 0001163653 srt:MaximumMember us-gaap:HedgeFundsMember 2024-04-01 2025-03-31 0001163653 nmr:AffiliateGroupMember 2024-04-01 2025-03-31 0001163653 nmr:AffiliatedCompaniesAndOtherEquityMethodInvesteesMember 2024-04-01 2025-03-31 0001163653 nmr:NSUsAndCSUsMember 2024-04-01 2025-03-31 0001163653 nmr:RSUandSARMember 2024-04-01 2025-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember 2024-04-01 2025-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember 2024-04-01 2025-03-31 0001163653 nmr:CreditDefaultIndicesMember 2024-04-01 2025-03-31 0001163653 us-gaap:CreditDefaultSwapMember 2024-04-01 2025-03-31 0001163653 nmr:OtherCommissionsMember 2024-04-01 2025-03-31 0001163653 nmr:CommissionsForDistributionOfInvestmentTrustMember 2024-04-01 2025-03-31 0001163653 nmr:BrokerageCommissionsMember 2024-04-01 2025-03-31 0001163653 nmr:OccupancyAndRelatedDepreciationMember 2024-04-01 2025-03-31 0001163653 nmr:InformationProcessingAndCommunicationsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:InvestmentTrustFundsAndOtherMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember nmr:PrivateEquityAndDebtInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember nmr:PrivateEquityAndDebtInvestmentsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDefaultRateMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRepoRateMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:PrivateEquityAndDebtInvestmentsMember 2024-04-01 2025-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2024-04-01 2025-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2024-04-01 2025-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2024-04-01 2025-03-31 0001163653 nmr:MacquarieManagementHoldingsIncMember 2024-04-01 2025-03-31 0001163653 nmr:NonBdEntitiesOtherThanInvestmentCompaniesMember 2024-04-01 2025-03-31 0001163653 srt:ParentCompanyMember 2024-04-01 2025-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2025-04-01 2026-03-31 0001163653 nmr:IndexOrEquityLinkedObligationsMember 2025-04-01 2026-03-31 0001163653 nmr:FloatingRateObligationsMember 2025-04-01 2026-03-31 0001163653 nmr:FixedRateObligationsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:OtherContractMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember 2025-04-01 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember 2025-04-01 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember 2025-04-01 2026-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:DerivativeMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2025-04-01 2026-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:SubtotalAssetsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:AdditionalPaidInCapitalMember 2025-04-01 2026-03-31 0001163653 srt:AsiaPacificMember 2025-04-01 2026-03-31 0001163653 srt:EuropeMember 2025-04-01 2026-03-31 0001163653 country:JP 2025-04-01 2026-03-31 0001163653 srt:AmericasMember 2025-04-01 2026-03-31 0001163653 nmr:SubtotalMember 2025-04-01 2026-03-31 0001163653 nmr:AllOtherAndEliminationsMember 2025-04-01 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:TradingAssetsExcludingDebtAndEquitySecuritiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:LongTermDebtMember 2025-04-01 2026-03-31 0001163653 nmr:CollateralizedFinancingMember 2025-04-01 2026-03-31 0001163653 us-gaap:AssetsMember 2025-04-01 2026-03-31 0001163653 nmr:PayablesAndDepositsMember 2025-04-01 2026-03-31 0001163653 us-gaap:ShortTermDebtMember 2025-04-01 2026-03-31 0001163653 nmr:CollateralizedAgreementsMember 2025-04-01 2026-03-31 0001163653 us-gaap:LoansReceivableMember 2025-04-01 2026-03-31 0001163653 nmr:OtherLiabilitiesMeasuredAtFairValueUsingTheFairValueOptionMember 2025-04-01 2026-03-31 0001163653 us-gaap:LiabilityMember 2025-04-01 2026-03-31 0001163653 nmr:InvestmentsAndOtherAssetsOtherMember 2025-04-01 2026-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2025-04-01 2026-03-31 0001163653 us-gaap:EquityMethodInvesteeMember 2025-04-01 2026-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2025-04-01 2026-03-31 0001163653 nmr:NSUsMember 2025-04-01 2026-03-31 0001163653 nmr:CSUsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueHedgingMember 2025-04-01 2026-03-31 0001163653 us-gaap:LongTermDebtMember us-gaap:FairValueHedgingMember 2025-04-01 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:DesignatedAsHedgingInstrumentMember 2025-04-01 2026-03-31 0001163653 us-gaap:DesignatedAsHedgingInstrumentMember 2025-04-01 2026-03-31 0001163653 us-gaap:NetInvestmentHedgingMember 2025-04-01 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NetInvestmentHedgingMember 2025-04-01 2026-03-31 0001163653 us-gaap:CreditRiskContractMember us-gaap:NondesignatedMember 2025-04-01 2026-03-31 0001163653 us-gaap:NondesignatedMember 2025-04-01 2026-03-31 0001163653 us-gaap:OtherContractMember us-gaap:NondesignatedMember 2025-04-01 2026-03-31 0001163653 us-gaap:InterestRateContractMember us-gaap:NondesignatedMember 2025-04-01 2026-03-31 0001163653 us-gaap:EquityContractMember us-gaap:NondesignatedMember 2025-04-01 2026-03-31 0001163653 us-gaap:ForeignExchangeContractMember us-gaap:NondesignatedMember 2025-04-01 2026-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember 2025-04-01 2026-03-31 0001163653 us-gaap:AccumulatedNetUnrealizedInvestmentGainLossMember 2025-04-01 2026-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember 2025-04-01 2026-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2025-04-01 2026-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember 2025-04-01 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember 2025-04-01 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember 2025-04-01 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-04-01 2026-03-31 0001163653 nmr:InvestmentManagementMember 2025-04-01 2026-03-31 0001163653 nmr:OtherSegmentMember 2025-04-01 2026-03-31 0001163653 us-gaap:CommercialPortfolioSegmentMember 2025-04-01 2026-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember 2025-04-01 2026-03-31 0001163653 nmr:LoansAtBanksMember 2025-04-01 2026-03-31 0001163653 us-gaap:RetainedEarningsMember 2025-04-01 2026-03-31 0001163653 country:GB us-gaap:ForeignCountryMember 2025-04-01 2026-03-31 0001163653 us-gaap:DomesticCountryMember 2025-04-01 2026-03-31 0001163653 country:US us-gaap:ForeignCountryMember 2025-04-01 2026-03-31 0001163653 nmr:SARPlanBMember 2025-04-01 2026-03-31 0001163653 nmr:WholesaleSegmentMember 2025-04-01 2026-03-31 0001163653 us-gaap:NoncontrollingInterestMember 2025-04-01 2026-03-31 0001163653 nmr:CounterpartyIssuedAClaimInTheEnglishCourtsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:NonJapanPlanMember 2025-04-01 2026-03-31 0001163653 us-gaap:TreasuryStockCommonMember 2025-04-01 2026-03-31 0001163653 nmr:OtherCommitmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember srt:MaximumMember 2025-04-01 2026-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember srt:MinimumMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:PrivateEquityAndPooledInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:InvestmentTrustFundsAndOtherMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:MinistryOfFinanceIndiaMember 2025-04-01 2026-03-31 0001163653 us-gaap:InlandRevenueSingaporeIRASMember 2025-04-01 2026-03-31 0001163653 us-gaap:NationalTaxAgencyJapanMember 2025-04-01 2026-03-31 0001163653 us-gaap:HerMajestysRevenueAndCustomsHMRCMember 2025-04-01 2026-03-31 0001163653 us-gaap:InternalRevenueServiceIRSMember 2025-04-01 2026-03-31 0001163653 nmr:BankingSegmentMember 2025-04-01 2026-03-31 0001163653 nmr:WealthManagementSegmentMember 2025-04-01 2026-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2025-04-01 2026-03-31 0001163653 us-gaap:RealEstateFundsMember 2025-04-01 2026-03-31 0001163653 us-gaap:VentureCapitalFundsMember 2025-04-01 2026-03-31 0001163653 us-gaap:HedgeFundsMember 2025-04-01 2026-03-31 0001163653 nmr:PrivateEquityFundsAndPrivateCreditFundsMember 2025-04-01 2026-03-31 0001163653 srt:MaximumMember us-gaap:HedgeFundsMember 2025-04-01 2026-03-31 0001163653 srt:MinimumMember us-gaap:HedgeFundsMember 2025-04-01 2026-03-31 0001163653 nmr:AffiliateGroupMember 2025-04-01 2026-03-31 0001163653 nmr:AffiliatedCompaniesAndOtherEquityMethodInvesteesMember 2025-04-01 2026-03-31 0001163653 nmr:NSUsAndCSUsMember 2025-04-01 2026-03-31 0001163653 nmr:RSUandSARMember 2025-04-01 2026-03-31 0001163653 nmr:NSUsMember 2025-04-01 2026-03-31 0001163653 nmr:OtherCreditRiskRelatedPortfolioProductsMember 2025-04-01 2026-03-31 0001163653 nmr:CreditriskRelatedOptionsAndSwaptionsMember 2025-04-01 2026-03-31 0001163653 us-gaap:CreditDefaultSwapMember 2025-04-01 2026-03-31 0001163653 nmr:CreditDefaultIndicesMember 2025-04-01 2026-03-31 0001163653 dei:AdrMember 2025-04-01 2026-03-31 0001163653 dei:BusinessContactMember 2025-04-01 2026-03-31 0001163653 us-gaap:CommonStockMember 2025-04-01 2026-03-31 0001163653 nmr:OtherCommissionsMember 2025-04-01 2026-03-31 0001163653 nmr:CommissionsForDistributionOfInvestmentTrustMember 2025-04-01 2026-03-31 0001163653 nmr:BrokerageCommissionsMember 2025-04-01 2026-03-31 0001163653 nmr:TwoThousandThirteenThroughTwoThousandTwentyTwoExpirationPeriodMember 2025-04-01 2026-03-31 0001163653 nmr:InformationProcessingAndCommunicationsMember 2025-04-01 2026-03-31 0001163653 nmr:OccupancyAndRelatedDepreciationMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember nmr:PrivateEquityAndDebtInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:MeasurementInputPriceEarningsRatioMember nmr:PrivateEquityAndDebtInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputEbitdaMultipleMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember nmr:RealEstateBackedSecuritiesMember 2025-04-01 2026-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDiscountRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputWeightedAverageCostCapitalMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputRiskFreeInterestRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRecoveryRateMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember us-gaap:MeasurementInputDiscountRateMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLongTermRevenueGrowthRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputCreditSpreadMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputRecoveryRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:MeasurementInputExpectedDividendPaymentMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember nmr:MeasurementInputCorrelationMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputRiskFreeInterestRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember nmr:MeasurementInputForeignExchangeVolatilityMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:MeasurementInputPriceVolatilityMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputRepoRateMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:MeasurementInputYieldsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputPrepaymentRateMember us-gaap:CollateralizedDebtObligationsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputDefaultRateMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputLossSeverityMember us-gaap:CollateralizedDebtObligationsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:MeasurementInputCreditSpreadMember us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:PrivateEquityAndDebtInvestmentsMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:MarketApproachValuationTechniqueMember nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:MarketApproachValuationTechniqueMember 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:RealEstateBackedSecuritiesMember 2025-04-01 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember us-gaap:ValuationTechniqueOptionPricingModelMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember us-gaap:ValuationTechniqueOptionPricingModelMember 2025-04-01 2026-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember us-gaap:ValuationTechniqueDiscountedCashFlowMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember nmr:DiscountCashFlowsValuationTechniqueAndOptionModelsMember us-gaap:FairValueInputsLevel3Member 2025-04-01 2026-03-31 0001163653 nmr:MacquarieManagementHoldingsIncMember 2025-04-01 2026-03-31 0001163653 country:IN us-gaap:ForeignCountryMember 2025-04-01 2026-03-31 0001163653 us-gaap:ForeignCountryMember 2025-04-01 2026-03-31 0001163653 us-gaap:StateAndLocalJurisdictionMember 2025-04-01 2026-03-31 0001163653 nmr:OthersMember us-gaap:StateAndLocalJurisdictionMember 2025-04-01 2026-03-31 0001163653 nmr:TokyoMember us-gaap:StateAndLocalJurisdictionMember 2025-04-01 2026-03-31 0001163653 srt:AffiliatedEntityMember us-gaap:LandAndBuildingMember 2025-04-01 2026-03-31 0001163653 nmr:NonBdEntitiesOtherThanInvestmentCompaniesMember 2025-04-01 2026-03-31 0001163653 srt:ParentCompanyMember 2025-04-01 2026-03-31 0001163653 nmr:OtherForeignMember us-gaap:ForeignCountryMember 2025-04-01 2026-03-31 0001163653 srt:EuropeMember 2024-03-31 0001163653 srt:AmericasMember 2024-03-31 0001163653 country:JP 2024-03-31 0001163653 nmr:SubtotalMember 2024-03-31 0001163653 srt:AsiaPacificMember 2024-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2024-03-31 0001163653 nmr:NSUsMember 2024-03-31 0001163653 nmr:CSUsMember 2024-03-31 0001163653 srt:MinimumMember nmr:BoardDirectorsMeetingHeldOnApril262023Member 2023-04-26 2023-04-26 0001163653 srt:MaximumMember nmr:BoardDirectorsMeetingHeldOnApril262023Member 2023-04-26 2023-04-26 0001163653 nmr:BoardDirectorsMeetingHeldOnApril262023Member 2023-04-26 2023-04-26 0001163653 nmr:BoardDirectorsMeetingHeldOnApril262023Member 2023-04-26 0001163653 srt:MinimumMember nmr:BoardOfDirectorsMeetingHeldOnJanuary312024Member 2024-01-31 2024-01-31 0001163653 srt:MaximumMember nmr:BoardOfDirectorsMeetingHeldOnJanuary312024Member 2024-01-31 2024-01-31 0001163653 nmr:BoardOfDirectorsMeetingHeldOnJanuary312024Member 2024-01-31 2024-01-31 0001163653 nmr:BoardOfDirectorsMeetingHeldOnJanuary312024Member 2024-01-31 0001163653 nmr:BoardOfDirectorsMeetingHeldOnApril252025Member 2025-04-25 0001163653 nmr:TwoActionsByFairfieldSentryLtdAndFairfieldSigmaLtdMember 2012-06-30 0001163653 nmr:ClaimFiledByMadoffTrusteeMember 2011-11-30 0001163653 nmr:ActionByAlkenFundSicavAlkenLuxembourgS.AMember 2018-01-01 2018-01-31 0001163653 nmr:ActionByYorkGlobalFinanceOffshoreBDHLuxembourgSarlNumberSeeminglyRelatedFundsMember 2019-05-01 2019-05-31 0001163653 nmr:ActionByEuropeanCommissionForInfringingTheCompetitionLawMember 2021-05-20 2021-05-20 0001163653 nmr:ActionByEuropeanCommissionForInfringingTheCompetitionLawMember 2025-03-01 2025-03-31 0001163653 nmr:ActionByFTSyndicateBanksMember 2017-09-01 2017-09-30 0001163653 nmr:ActionByFTSyndicateBanksMember 2017-09-30 0001163653 nmr:ActionByFTSyndicateBanksMember 2023-11-01 2023-11-30 0001163653 nmr:ActionByBombayHighCourtMember 2022-08-01 2022-08-31 0001163653 srt:MinimumMember nmr:BoardOfDirectorsMeetingHeldOnApril252025Member 2025-04-25 2025-04-25 0001163653 srt:MaximumMember nmr:BoardOfDirectorsMeetingHeldOnApril252025Member 2025-04-25 2025-04-25 0001163653 nmr:BoardOfDirectorsMeetingHeldOnApril252025Member 2025-04-25 2025-04-25 0001163653 nmr:MacquarieManagementHoldingsIncMember 2025-12-01 0001163653 us-gaap:ComputerSoftwareIntangibleAssetMember nmr:MacquarieManagementHoldingsIncMember 2025-12-01 0001163653 us-gaap:CustomerRelationshipsMember nmr:MacquarieManagementHoldingsIncMember 2025-12-01 0001163653 nmr:MacquarieManagementHoldingsIncMember 2025-12-01 2025-12-01 0001163653 nmr:BoardOfDirectorsMeetingHeldOnJanuary302026Member 2026-01-30 0001163653 srt:MinimumMember nmr:BoardOfDirectorsMeetingHeldOnJanuary302026Member 2026-01-30 2026-01-30 0001163653 srt:MaximumMember nmr:BoardOfDirectorsMeetingHeldOnJanuary302026Member 2026-01-30 2026-01-30 0001163653 nmr:BoardOfDirectorsMeetingHeldOnJanuary302026Member 2026-01-30 2026-01-30 0001163653 us-gaap:SubsequentEventMember 2026-06-22 0001163653 us-gaap:RestrictedStockUnitsRSUMember srt:MaximumMember 2026-05-14 2026-05-14 0001163653 us-gaap:RestrictedStockUnitsRSUMember srt:MinimumMember 2026-05-14 2026-05-14 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2026-05-14 2026-05-14 0001163653 us-gaap:PerformanceSharesMember 2026-05-14 0001163653 us-gaap:PerformanceSharesMember srt:MaximumMember 2026-05-14 0001163653 nmr:NSUsMember 2026-05-25 2026-05-25 0001163653 nmr:ActionByProsecutorOfTheCourtOfAuditorsInItalyMember 2024-10-31 0001163653 nmr:MacquarieManagementHoldingsIncMember 2024-04-01 2024-04-01 0001163653 nmr:MacquarieManagementHoldingsIncMember us-gaap:EmployeeSeveranceMember 2024-04-01 2024-04-01 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember 2023-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2023-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember 2023-03-31 0001163653 us-gaap:NoncontrollingInterestMember 2023-03-31 0001163653 us-gaap:CommonStockMember 2023-03-31 0001163653 us-gaap:TreasuryStockCommonMember 2023-03-31 0001163653 us-gaap:RetainedEarningsMember 2023-03-31 0001163653 us-gaap:AdditionalPaidInCapitalMember 2023-03-31 0001163653 us-gaap:CommercialPortfolioSegmentMember 2023-03-31 0001163653 nmr:LoansAtBanksMember 2023-03-31 0001163653 us-gaap:CommercialPortfolioSegmentMember 2024-03-31 0001163653 nmr:LoansAtBanksMember 2024-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember 2024-03-31 0001163653 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2024-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember 2024-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2024-03-31 0001163653 us-gaap:RetainedEarningsMember 2024-03-31 0001163653 us-gaap:TreasuryStockCommonMember 2024-03-31 0001163653 us-gaap:ParentMember 2024-03-31 0001163653 us-gaap:NoncontrollingInterestMember 2024-03-31 0001163653 us-gaap:CommonStockMember 2024-03-31 0001163653 us-gaap:AdditionalPaidInCapitalMember 2024-03-31 0001163653 srt:ParentCompanyMember 2023-03-31 0001163653 srt:ParentCompanyMember 2024-03-31 0001163653 us-gaap:AccumulatedNetUnrealizedInvestmentGainLossMember 2024-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:InvestmentsAndOtherAssetsOtherMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:OtherContractMember 2024-03-31 0001163653 nmr:PrivateEquityAndDebtInvestmentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 nmr:BankAndCorporateDebtSecuritiesAndLoansForTradingPurposeMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 nmr:RealEstateBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquityContractMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:DerivativeMember 2024-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LoansReceivableMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:CollateralizedAgreementsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:SubtotalAssetsMember 2024-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:InterestRateContractMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CreditRiskContractMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignExchangeContractMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:NonTradingDebtSecuritiesMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2024-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:PayablesAndDepositsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ShortTermDebtMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:OtherLiabilitiesOtherMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:LongTermDebtMember 2024-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2024-03-31 0001163653 nmr:WholesaleSegmentMember 2024-03-31 0001163653 nmr:OtherSegmentMember 2024-03-31 0001163653 nmr:ShortTermSecuredMarginLoansMember 2024-03-31 0001163653 nmr:WholesaleSegmentMember 2025-03-31 0001163653 nmr:OtherSegmentMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:PrivateEquityAndPooledInvestmentsMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member nmr:InvestmentTrustFundsAndOtherMember 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member 2024-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:DerivativeMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:OtherContractMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:SubtotalAssetsMember 2025-03-31 0001163653 nmr:JapaneseAgencyAndMunicipalDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2025-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-03-31 0001163653 nmr:InvestmentTrustFundsAndOtherMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2025-03-31 0001163653 us-gaap:RetainedEarningsMember 2025-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember 2025-03-31 0001163653 us-gaap:AccumulatedNetUnrealizedInvestmentGainLossMember 2025-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember 2025-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2025-03-31 0001163653 us-gaap:AdditionalPaidInCapitalMember 2025-03-31 0001163653 us-gaap:NoncontrollingInterestMember 2025-03-31 0001163653 us-gaap:TreasuryStockCommonMember 2025-03-31 0001163653 us-gaap:ParentMember 2025-03-31 0001163653 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2025-03-31 0001163653 us-gaap:CommonStockMember 2025-03-31 0001163653 nmr:CSUsMember 2025-03-31 0001163653 nmr:NSUsMember 2025-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2025-03-31 0001163653 nmr:CSUsMember 2026-03-31 0001163653 nmr:NSUsMember 2026-03-31 0001163653 us-gaap:RestrictedStockUnitsRSUMember 2026-03-31 0001163653 nmr:WholesaleSegmentMember 2026-03-31 0001163653 nmr:InvestmentManagementMember 2026-03-31 0001163653 nmr:OtherSegmentMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:DerivativeMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:OtherContractMember 2026-03-31 0001163653 us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:TradingAssetsAndPrivateEquityInvestmentsMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember nmr:SubtotalAssetsMember 2026-03-31 0001163653 us-gaap:CorporateDebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2026-03-31 0001163653 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2026-03-31 0001163653 us-gaap:CollateralizedDebtObligationsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2026-03-31 0001163653 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:TradingLiabilitiesMember 2026-03-31 0001163653 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2026-03-31 0001163653 us-gaap:RetainedEarningsMember 2026-03-31 0001163653 us-gaap:AccumulatedNetUnrealizedInvestmentGainLossMember 2026-03-31 0001163653 nmr:AccumulatedOwnCreditAdjustmentsAttributableToParentMember 2026-03-31 0001163653 us-gaap:AccumulatedTranslationAdjustmentMember 2026-03-31 0001163653 us-gaap:AdditionalPaidInCapitalMember 2026-03-31 0001163653 us-gaap:TreasuryStockCommonMember 2026-03-31 0001163653 us-gaap:NoncontrollingInterestMember 2026-03-31 0001163653 us-gaap:ParentMember 2026-03-31 0001163653 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2026-03-31 0001163653 us-gaap:CommonStockMember 2026-03-31 iso4217:JPY xbrli:shares xbrli:pure utr:Year iso4217:USD iso4217:EUR iso4217:INR utr:Day iso4217:JPY xbrli:shares nmr:Segment nmr:Securities\n\n \n\nUNITED STATES\n\nSECURITIES AND EXCHANGE COMMISSION\n\nWashington, D.C. 20549\n\n \n\n \n\nFORM\n20-F\n\n \n\n \n\n☐\n\nREGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nOR\n\n☒\n\nANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the fiscal year ended March 31, 2026\n\nOR\n\n☐\n\nTRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the transition period from   to   \n\nOR\n\n☐\n\nSHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nDate of event re\nquiri\nng this shell company report\n\nCommission file number:\n1-15270\n\n \n\n \n\nNomura Horudingusu Kabushiki Kaisha\n\n(Exact name of registrant as specified in its charter)\n\n \n\n \n\nNomura Holdings, Inc.\n\n(Translation of registrant’s name into English)\n\n \n\n \n\n \n\nJapan\n\n  \n\n13-1,\nNihonbashi\n1-chome\n\nChuo-ku,\nTokyo\n103-8645\n\nJapan\n\n(Jurisdiction of incorporation or organization)\n\n  \n\n(Address of principal executive offices)\n\nHiroyuki Moriuchi,\n\n81-3-5255-1000,\n\n81-3-6746-7850\n\n(Name, Telephone,\nE-mail\nand/or Facsimile number and Address of Company Contact Person)\n\n \n\n \n\nSecurities registered or to be registered pursuant to Section 12(b) of the Act:\n\n \n\nTitle of Each Class\n\n \n\nTrading Symbol(s)\n\n \n\nName of Each Exchange On Which Registered\n\nAmerican Depositary Shares\n\nCommon Stock\n\n*\n\n \n\nNMR\n\n \n\nNew York Stock Exchange\n\n \n\n*\n\nNot for trading, but only in connection with the registration of the American Depositary Shares, each representing one share of Common Stock.\n\nSecurities registered or to be registered pursuant to Section 12(g) of the Act:\n\nNone\n\n(Title of Class)\n\nSecurities for which there is a reporting obligation pursuant to Section 15(d) of the Act:\n\nNone\n\n(Title of Class)\n\n \n\n \n\nIndicate the number of outstanding shares of each of the iss\nuer’s classes of capital or common stock as of the close of the period covered by the annual report.\n\nAs of March 31, 2026,\n\n2,901,337,224\n\nshares of Common Stock were outstanding, including\n\n79,924,681\n\nshares represented by 79,924,681 American Depositary Shares.\n\nIndicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ☒ Yes \n\n☐  No\n\nIf this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. ☐ Yes ☒ No\n\nIndicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐\n\nIndicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation\nS-T\n(§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐\n\nIndicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a\nnon-accelerated\nfiler, or an emerging growth company. See definition of “large accelerated filer,” “accelerated filer,” and “emerging growth company” in Rule\n12b-2\nof the Exchange Act. (Check one):\n\n \n\nLarge accelerated filer ☒\n  \nAccelerated filer ☐\n  \n\nNon-accelerated\nfiler ☐\n\n \n\n \n\n \n\n \n\nEmerging growth company ☐\n\nIf an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards† provided pursuant to Section 13(a) of the Exchange Act. ☐\n\n† The term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012.\n\nIndicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒\n\nIf securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐\n\nIndicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to\n§240.10D-1(b). ☐\n\nIndicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing:\n\n \n\nU.S. GAAP\n\n ☒\n\n  \n\nInternational Financial Reporting Standards as issued\n\nby the International Accounting Standards Board \n\n☐\n\n  \n\nOther\n ☐\n\nIf “Other” has been checked in response to the previous question, indicate by check mark which financial\nstatement\nitem the registrant has elected to follow. ☐ Item 17 ☐ Item 18\n\nIf this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule\n12b-2\nof the Exchange Act). ☐ Yes ☒ No\n\n(APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY PROCEEDINGS DURING THE PAST FIVE YEARS)\n\nIndicate by check mark whether the registrant has filed all documents and reports required to be filed by Sections 12, 13 or 15(d) of the Securities Exchange Act of 1934 subsequent to the distribution of securities\n\nunder a plan confirmed by a court. ☐ Yes ☐ No\n\n \n\n \n\n \n\n \n\n##### Table of Contents\n\nTABLE OF CONTENTS\n\n \n\n \n \n \n  \nPage\n\n \nPART I"}