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Derivative Instruments and Hedging Activities - Derivative Assets and Liabilities at Fair Value (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | $ 294,039 | $ 227,801
Derivative assets, gross amount | 2,675 | 3,098
Derivative liabilities, gross amount | 2,932 | 4,550
Derivative Asset, netting adjustments | (1,005) | (1,134)
Derivative Liability, netting adjustments | (597) | (1,235)
Net Amounts as Recognized | 1,670 | 1,964
Net Amounts as Recognized | 2,335 | 3,315
Net valuation allowance on derivative assets and liabilities for non-performance risk | 2 | 4
Derivatives designated as accounting hedges: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 148,075 | 98,966
Derivative assets, gross amount | 235 | 85
Derivative liabilities, gross amount | 317 | 820
Derivatives designated as accounting hedges: | Interest rate contracts: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 139,337 | 91,306
Derivative assets, gross amount | 234 | 3
Derivative liabilities, gross amount | 49 | 504
Derivatives designated as accounting hedges: | Interest rate contracts: | Fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 68,987 | 60,956
Derivative assets, gross amount | 18 | 3
Derivative liabilities, gross amount | 26 | 53
Derivatives designated as accounting hedges: | Interest rate contracts: | Cash flow hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 70,350 | 30,350
Derivative assets, gross amount | 216 | 0
Derivative liabilities, gross amount | 23 | 451
Derivatives designated as accounting hedges: | Foreign exchange and other contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 8,738 | 7,660
Derivative assets, gross amount | 1 | 82
Derivative liabilities, gross amount | 268 | 316
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 1,380 | 1,338
Derivative assets, gross amount | 0 | 0
Derivative liabilities, gross amount | 113 | 211
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Cash flow hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 2,488 | 2,175
Derivative assets, gross amount | 0 | 4
Derivative liabilities, gross amount | 66 | 14
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Net investment hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 4,870 | 4,147
Derivative assets, gross amount | 1 | 78
Derivative liabilities, gross amount | 89 | 91
Derivatives not designated as accounting hedges: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 145,964 | 128,835
Derivative assets, gross amount | 2,440 | 3,013
Derivative liabilities, gross amount | 2,615 | 3,730
Derivatives not designated as accounting hedges: | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 142,137 | 125,462
Derivative assets, gross amount | 2,399 | 2,970
Derivative liabilities, gross amount | 2,576 | 3,689
Derivatives not designated as accounting hedges: | Interest rate contracts: | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 103,489 | 91,601
Derivative assets, gross amount | 1,188 | 1,140
Derivative liabilities, gross amount | 1,382 | 1,873
Derivatives not designated as accounting hedges: | Interest rate contracts: | Other interest rate exposures |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 872 | 1,135
Derivative assets, gross amount | 21 | 34
Derivative liabilities, gross amount | 31 | 22
Derivatives not designated as accounting hedges: | Foreign exchange and other contracts | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 5,153 | 4,926
Derivative assets, gross amount | 50 | 74
Derivative liabilities, gross amount | 47 | 78
Derivatives not designated as accounting hedges: | Commodity contracts | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 33,495 | 28,935
Derivative assets, gross amount | 1,161 | 1,756
Derivative liabilities, gross amount | 1,147 | 1,738
Derivatives not designated as accounting hedges: | Other contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 2,955 | 2,238
Derivative assets, gross amount | 20 | 9
Derivative liabilities, gross amount | $ 8 | $ 19

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