Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Balances of Policy Account (Detail) - Fixed Annuity And Annuitization Benefits - JPY (¥) ¥ in Millions |
6 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2026 |
Mar. 31, 2026 |
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| Policyholder Account Balance [Line Items] | ||
| Beginning balance | ¥ 101,782 | ¥ 119,093 |
| Transfer in | 2,758 | 9,865 |
| Surrenders and partial surrenders | (19) | (112) |
| Benefit payments and lump sum payments, etc. | (12,308) | (27,213) |
| Policy charges | (98) | (203) |
| Transfer out | (65) | (393) |
| Interests | 354 | 786 |
| Others | (20) | (41) |
| Ending balance | ¥ 92,384 | ¥ 101,782 |
| Weighted average guaranteed interest rate (%) | 0.70% | 0.70% |
| Benefits in excess of policy account balances (Millions of yen) | ¥ 0 | ¥ 0 |
| Cash surrender value (Millions of yen) | ¥ 87,213 | ¥ 96,433 |
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- Definition Transfer from policyholder account balance to separate account. No definition available.
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- Definition Transfer to policyholder account balance from separate account. No definition available.
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- Definition Amount of cash to be paid to policyholder upon termination and surrender of long-duration contract issued by insurance entity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of interest expense for allocation to policyholder account balance. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash outflow to policyholder account balance from benefit payment. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of increase (decrease) in liability for policyholder account balance from change, classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of guaranteed benefit in excess of current account balance of policyholder account balance. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of decrease in liability for policyholder account balance from policy charge. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of decrease in liability for policyholder account balance from contract redemption. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Weighted-average crediting rate for liability for policyholder account balance, calculated at a point in time. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount due to policyholder. Includes, but is not limited to, unpaid policy dividend, retrospective refund, and undistributed earnings on participating business. Excludes future policy benefit and claim expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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