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Loans, Held For Sale, Input, Range.

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Loans, Held For Sale, Input, Weighted Average.

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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

Remaining period of expected liquidation by investee of underlying asset of investment measured at net asset value per share or unit. In 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

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- Definition

Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

+ References

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

+ References

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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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- Definition

Value of input used to measure loan, held for sale.

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Fair Value - Additional Information (Detail)	12 Months Ended
Fair Value - Additional Information (Detail)	Mar. 31, 2026 JPY (¥)	Mar. 31, 2025 JPY (¥)	Mar. 31, 2024 JPY (¥)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-sale, measurement input		80
Carrying amounts of other equity interests of which fair value is not readily determinable	¥ 687,000,000,000	¥ 602,000,000,000
Loans, Held For Sale, Input, Weighted Average	77.7
Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans, Held For Sale, Input, Range	83.9
Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans, Held For Sale, Input, Range	74.5
Senior borrowings and bonds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
The differences between the aggregate fair value and aggregate unpaid principal balance of the notes for which the fair value option has been elected	¥ 226,000,000,000	109,000,000,000
Net unrealized gains (losses) resulting from changes in fair values of the notes	¥ 147,000,000,000	7,000,000,000	¥ (48,000,000,000)
Investment funds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Underlying assets, estimated remaining liquidation period	10 years
Long-term debt
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of liabilities transferred into Level 3	¥ 41,000,000,000	7,000,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3	41,000,000,000	7,000,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3	5,000,000,000
Trading securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	20,000,000,000
Available-for-sale securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of assets transferred out of Level 3	3,000,000,000	11,000,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	3,000,000,000	11,000,000,000
Derivative financial instruments assets
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of assets transferred out of Level 3	1,000,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	6,000,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	¥ 1,000,000,000
Other investments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of assets transferred out of Level 3		2,000,000,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		¥ 2,000,000,000