Credit Quality of Financial Assets and the Allowance for Credit Losses - Additional Information (Detail) - Installment Loans - JPY (¥) ¥ in Millions	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Modifications [Line Items]
Repurchase	¥ 76,395	¥ 48,855	¥ 14,362
Loans for which real estate is received as collateral
Financing Receivable, Modifications [Line Items]
Mortgage loans in process of foreclosure	¥ 107	¥ 79

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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- Definition

Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

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