Other assets - Tax Credit Investments (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Other Assets [Abstract] | ||
| Tax credit investments | $ 3,055 | $ 3,151 |
| Tax credit investments, commitment | $ 880 | $ 946 |
| Duration for funding future investments | 5 years |
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- Definition Investment Program, Proportional Amortization Method, Elected, Commitment, Duration For Funding No definition available.
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- Definition Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- References No definition available.
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- Definition Amount of commitment and contingent commitment, including amount of delayed equity contribution, for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, commitment and contingent commitment related to investment under tax credit program not meeting condition for accounting under proportional amortization method. Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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