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Commitments, Contingent Liabilities, and Guarantees - Commitments to Extend Credit or Funding (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Guarantor Obligations [Line Items] |  |
Total loan commitments | $ 75,085 | $ 79,076
Commercial letters of credit | 65 | 86
Purchase card commitments | 995 | 875
Principal investing commitments | 1 | 9
Tax credit investment commitments | 1,361 | 958
Total loan and other commitments | 77,507 | 81,004
Commercial and other |  |
Guarantor Obligations [Line Items] |  |
Total loan commitments | 55,603 | 58,269
Commercial real estate and construction |  |
Guarantor Obligations [Line Items] |  |
Total loan commitments | 3,440 | 4,037
Home equity |  |
Guarantor Obligations [Line Items] |  |
Total loan commitments | 8,984 | 9,346
Credit cards |  |
Guarantor Obligations [Line Items] |  |
Total loan commitments | $ 7,058 | $ 7,424

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- Definition Loan and Other Commitments + References No definition available. + Details
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