Investments - Summary of Equity Securities Without Readily Determinable Fair Values (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
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| Equity Securities without Readily Determinable Fair Value [Line Items] | |||
| Carrying amounts at the end of the period | ¥ 686,545 | ¥ 601,621 | ¥ 357,938 |
| Downward adjustments and impairments | 28,869 | 23,886 | 11,002 |
| Upward adjustments | ¥ 13,713 | ¥ 13,880 | ¥ 13,764 |
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- Definition Amount of investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cumulative loss from downward price adjustment on investment in equity security without readily determinable fair value. 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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- Definition Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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