Collateralized transactions - Assets owned, pledged as collateral ,primarily to stock exchanges and clearing organizations (Detail) - JPY (¥)
¥ in Millions

Mar. 31, 2026

Mar. 31, 2025

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

¥ 4,082,645

¥ 4,207,389

Non-trading debt securities

^[1]

21,566

15,896

Investments in and advances to affiliated companies

^[2]

16,086

16,124

Equities and convertible securities [Member]

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

417,915

326,398

Government and government agency securities [Member]

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

1,396,517

1,134,816

Bank and corporate debt securities [Member]

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

123,674

86,034

Commercial mortgage-backed securities ("CMBS") [Member]

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

5,189

Residential mortgage-backed securities ("RMBS") [Member]

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

2,120,771

2,626,708

Collateralized debt obligations ("CDOs") and other [Member]

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

^[3]

7,864

12,391

Investment trust funds and other [Member]

Financial Instruments Owned and Pledged as Collateral [Line Items]

Trading assets

¥ 10,715

¥ 21,042

[1]	Non-trading debt securities are primarily Japanese municipal securities issued by prefectures or ordinance-designated city.
[2]	Investments in and advances to affiliated companies comprise shares in Nomura Research Institute, Ltd.
[3]	Includes collateralized loan obligations (“CLOs”) and asset-backed securities (“ABSs”) such as those secured on credit card loans, auto loans and student loans.