Derivative Financial Instruments - Additional Information (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Derivative [Line Items] | ||
| Cash collateral provided and not offset against derivative positions and included in Other assets | ¥ 2,305,536 | ¥ 1,666,564 |
| Cash collateral accepted and not offset against derivative positions and included in Other liabilities | 2,163,341 | 1,380,243 |
| Mizuho Financial Group, Inc. | ||
| Derivative [Line Items] | ||
| Cash collateral provided and not offset against derivative positions and included in Other assets | ¥ 2,306,000 | ¥ 1,667,000 |
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- Definition Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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/2009/role/commonPracticeRef
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- Details
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