v3.26.1
Installment Loans (Composition of Installment Loans By Domicile and Type of Borrower) (Detail) - JPY (¥)
¥ in Millions
Mar. 31, 2026
Mar. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans ¥ 4,173,582 ¥ 4,081,019
Equity method investees    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 20,543 131,476
Purchased loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans [1] 16,214 21,389
Japan | Consumer borrowers    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 2,059,602 1,976,927
Japan | Consumer borrowers | Real estate loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 1,989,371 1,901,794
Japan | Consumer borrowers | Card loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 64,600 67,874
Japan | Consumer borrowers | Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 5,631 7,259
Japan | Corporate borrowers    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 1,033,224 950,413
Japan | Corporate borrowers | Real estate companies    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 461,006 415,666
Japan | Corporate borrowers | Non-recourse loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 343,121 301,477
Japan | Corporate borrowers | Commercial, industrial and other companies    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 229,097 233,270
Overseas | Consumer borrowers    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 77,424 94,194
Overseas | Consumer borrowers | Real estate loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 38,122 55,022
Overseas | Consumer borrowers | Other    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 39,302 39,172
Overseas | Corporate borrowers    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 966,575 906,620
Overseas | Corporate borrowers | Real estate companies    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans [2] 216,272 228,793
Overseas | Corporate borrowers | Non-recourse loans    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans 200,308 86,724
Overseas | Corporate borrowers | Commercial, industrial and other companies    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Installment loans ¥ 549,995 ¥ 591,103
[1] Purchased loans represent loans with evidence of deterioration of credit quality since origination and for which it is probable at acquisition that collection of all contractually required payments from the debtors is unlikely.
[2] Includes the outstanding balance of loans that were previously sold with a repurchase option and are recorded as assets for accounting purposes in accordance with ASC 860 (“Transfers and Servicing”.)