Pension and Other Postretirement Employee Benefit Plans - Net Periodic Benefit Costs and Fair Value of Plan Assets (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Retirement Benefits [Abstract] | ||||
| Total net periodic defined benefit plan credit | $ (50) | $ (67) | $ (176) | $ (195) |
| Total defined contribution plans | 508 | 506 | 1,438 | 1,454 |
| Total pension and OPEB cost included in noninterest expense | 458 | $ 439 | 1,262 | $ 1,259 |
| Pension settlement losses | $ 56 | $ 117 | ||
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- References No definition available.
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost (reversal of cost) for pension and other postretirement benefits. No definition available.
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