Severance Indemnities and Pension Plans (Assumed Health Care Cost Trend Rates and Effect of a One-percentage-point Change for Foreign Offices and Subsidiaries) (Detail) |
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Retirement Benefits [Abstract] | ||
| Initial trend rate | 9.25% | 8.00% |
| Ultimate trend rate | 4.00% | 4.00% |
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- References No definition available.
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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