Income Taxes - Summary of Unrecognized Deferred Tax Assets on Tax Credit Carryforward (Detail) - JPY (¥) ¥ in Millions |
Mar. 31, 2025 |
Mar. 31, 2024 |
|---|---|---|
| Disclosure details of carry forward details of tax credits unutilised for which no deferred tax assets are recognized [Line items] | ||
| Tax credit carryforwards | ¥ 61,687 | ¥ 95,462 |
| Within 5 years [Member] | ||
| Disclosure details of carry forward details of tax credits unutilised for which no deferred tax assets are recognized [Line items] | ||
| Tax credit carryforwards | 3,778 | 4,764 |
| Between 5 and 10 years [Member] | ||
| Disclosure details of carry forward details of tax credits unutilised for which no deferred tax assets are recognized [Line items] | ||
| Tax credit carryforwards | 3,878 | 3,680 |
| Later than 10 years [Member] | ||
| Disclosure details of carry forward details of tax credits unutilised for which no deferred tax assets are recognized [Line items] | ||
| Tax credit carryforwards | ¥ 54,031 | ¥ 87,018 |