Income Taxes - Components by Expiry of Carryforward of Unused Tax Credits for which Deferred Tax Assets are not Recognized (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
|---|---|---|
| Disclosure of temporary difference, unused tax losses and unused tax credits [line items] | ||
| Unused tax credit | ¥ 377 | ¥ 124,850 |
| Within 1 year [member] | ||
| Disclosure of temporary difference, unused tax losses and unused tax credits [line items] | ||
| Unused tax credit | 23 | 4 |
| Between 1 and 5 years [member] | ||
| Disclosure of temporary difference, unused tax losses and unused tax credits [line items] | ||
| Unused tax credit | 354 | 124,831 |
| Between 5 and 20 years [member] | ||
| Disclosure of temporary difference, unused tax losses and unused tax credits [line items] | ||
| Unused tax credit | 15 | |
| Indefinite periods [member] | ||
| Disclosure of temporary difference, unused tax losses and unused tax credits [line items] | ||
| Unused tax credit |