Income Taxes (Detail of Current and Deferred Income Tax Expense (Benefit)) (Detail) - JPY (¥) ¥ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
|
| Current: | |||
| Domestic | ¥ 118,433 | ¥ 106,951 | ¥ 250,780 |
| Foreign | 241,724 | 302,494 | 203,213 |
| Total | 360,157 | 409,445 | 453,993 |
| Deferred: | |||
| Domestic | 103,533 | 87,990 | (346,367) |
| Foreign | 64,248 | 3,222 | (60,875) |
| Total | 167,781 | 91,212 | (407,242) |
| Income tax expense | (527,938) | (500,657) | (46,751) |
| Income tax expense (benefit) reported in Accumulated OCI relating to: | |||
| Investment securities | (46,184) | 33,327 | (59,568) |
| Debt valuation adjustments | 4,941 | (19,707) | 7,858 |
| Derivatives qualifying for cash flow hedges | (436) | (120) | (2,268) |
| Defined benefit plans | 32,952 | 170,191 | (10,301) |
| Foreign currency translation adjustments | (11,455) | 155,814 | 85,074 |
| Other Comprehensive Income (Loss), Tax (expense) or benefit | (20,182) | 339,505 | 20,795 |
| Total | ¥ 507,756 | ¥ 840,162 | ¥ 67,546 |
| X | ||||||||||
- Definition Amount of current federal, state, and local tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current national, regional, territorial, and provincial tax expense (benefit) for non-US (United States of America) jurisdiction. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of deferred federal, state, and local tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, deferred national, regional, territorial, and provincial tax expense (benefit) for non-US (United States of America) jurisdiction. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of income tax expense (benefit) for continuing operations, discontinued operations, other comprehensive income, and items charged (credited) directly to shareholders' equity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount, after adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount, after reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount, after reclassification adjustment, of tax expense (benefit) of gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of tax expense (benefit) allocated to other comprehensive income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
|