v3.26.1
Financial Instruments - Schedule of Carrying Amount of Assets Pledged as Collateral (Parenthetical) (Details) - JPY (¥)
¥ in Millions
Mar. 31, 2026
Mar. 31, 2025
Disclosure of financial assets [line items]    
Loans and advances to customers ¥ 2,512,851 ¥ 1,927,607
Borrowings From Securitization Backed    
Disclosure of financial assets [line items]    
Loans and advances to customers ¥ 55,000 ¥ 55,000