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Derivative Instruments and Hedging Activities - Derivative Assets and Liabilities at Fair Value (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | $ 325,778 | $ 294,039
Derivative assets, gross amount | 2,232 | 2,675
Derivative liabilities, gross amount | 2,032 | 2,932
Derivative Asset, netting adjustments | (1,056) | (1,005)
Derivative Liability, netting adjustments | (304) | (597)
Net Amounts as Recognized | 1,176 | 1,670
Net Amounts as Recognized | 1,728 | 2,335
Net valuation allowance on derivative assets and liabilities for non-performance risk | 1 | 2
Derivatives designated as accounting hedges: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 171,725 | 148,075
Derivative assets, gross amount | 390 | 235
Derivative liabilities, gross amount | 138 | 317
Derivatives designated as accounting hedges: | Interest rate contracts: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 163,800 | 139,337
Derivative assets, gross amount | 126 | 234
Derivative liabilities, gross amount | 37 | 49
Derivatives designated as accounting hedges: | Interest rate contracts: | Fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 61,250 | 68,987
Derivative assets, gross amount | 3 | 18
Derivative liabilities, gross amount | 13 | 26
Derivatives designated as accounting hedges: | Interest rate contracts: | Cash flow hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 102,550 | 70,350
Derivative assets, gross amount | 123 | 216
Derivative liabilities, gross amount | 24 | 23
Derivatives designated as accounting hedges: | Foreign exchange and other contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 7,925 | 8,738
Derivative assets, gross amount | 264 | 1
Derivative liabilities, gross amount | 101 | 268
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 518 | 1,380
Derivative assets, gross amount | 0 | 0
Derivative liabilities, gross amount | 101 | 113
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Cash flow hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 2,549 | 2,488
Derivative assets, gross amount | 74 | 0
Derivative liabilities, gross amount | 0 | 66
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Net investment hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 4,858 | 4,870
Derivative assets, gross amount | 190 | 1
Derivative liabilities, gross amount | 0 | 89
Derivatives not designated as accounting hedges: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 154,053 | 145,964
Derivative assets, gross amount | 1,842 | 2,440
Derivative liabilities, gross amount | 1,894 | 2,615
Derivatives not designated as accounting hedges: | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 149,890 | 142,137
Derivative assets, gross amount | 1,803 | 2,399
Derivative liabilities, gross amount | 1,880 | 2,576
Derivatives not designated as accounting hedges: | Interest rate contracts: | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 108,754 | 103,489
Derivative assets, gross amount | 865 | 1,188
Derivative liabilities, gross amount | 1,014 | 1,382
Derivatives not designated as accounting hedges: | Interest rate contracts: | Other interest rate exposures |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 909 | 872
Derivative assets, gross amount | 14 | 21
Derivative liabilities, gross amount | 9 | 31
Derivatives not designated as accounting hedges: | Foreign exchange and other contracts | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 6,951 | 5,153
Derivative assets, gross amount | 80 | 50
Derivative liabilities, gross amount | 52 | 47
Derivatives not designated as accounting hedges: | Commodity contracts | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 34,185 | 33,495
Derivative assets, gross amount | 858 | 1,161
Derivative liabilities, gross amount | 814 | 1,147
Derivatives not designated as accounting hedges: | Other contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 3,254 | 2,955
Derivative assets, gross amount | 25 | 20
Derivative liabilities, gross amount | $ 5 | $ 8

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