Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Single-Payment Whole Life Insurance (Detail) - Whole Life Insurance [Member] - JPY (¥) ¥ in Millions |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Liability for Future Policy Benefit, Activity [Line Items] | ||
| Beginning balance | ¥ 134,572 | ¥ 0 |
| New contract | 148,468 | 136,863 |
| Surrenders and partial surrenders | (6,555) | (66) |
| Benefit payments and lump sum payments, etc. | (950) | (49) |
| Policy charges | (2,107) | (188) |
| Interests | 11,793 | 1,072 |
| Effect of changes in foreign exchange rate | 19,320 | (3,060) |
| Ending balance | ¥ 304,541 | ¥ 134,572 |
| Weighted average guaranteed interest rate | 5.50% | 3.90% |
| Benefits in excess of policy account balances | ¥ 0 | ¥ 0 |
| Cash surrender value | ¥ 292,731 | ¥ 127,659 |
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- Definition Policyholder net exchange rate fluctuations. 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 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 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 in liability for policyholder account balance from contract issuance. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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