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Derivative Instruments and Hedging Activities - Derivative Assets and Liabilities at Fair Value (Details) - USD ($) $ in Millions | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | $ 349,550 | $ 325,778
Derivative assets, gross amount | 2,419 | 2,232
Derivative liabilities, gross amount | 2,462 | 2,032
Derivative Asset, netting adjustments | (532) | (1,056)
Derivative Liability, netting adjustments | (776) | (304)
Net Amounts as Recognized | 1,887 | 1,176
Net Amounts as Recognized | 1,686 | 1,728
Net valuation allowance on derivative assets and liabilities for non-performance risk | 5 | 1
Derivatives designated as accounting hedges: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 176,302 | 171,725
Derivative assets, gross amount | 267 | 390
Derivative liabilities, gross amount | 392 | 138
Derivatives designated as accounting hedges: | Interest rate contracts: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 167,722 | 163,800
Derivative assets, gross amount | 267 | 126
Derivative liabilities, gross amount | 12 | 37
Derivatives designated as accounting hedges: | Interest rate contracts: | Fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 60,472 | 61,250
Derivative assets, gross amount | 47 | 3
Derivative liabilities, gross amount | 8 | 13
Derivatives designated as accounting hedges: | Interest rate contracts: | Cash flow hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 107,250 | 102,550
Derivative assets, gross amount | 220 | 123
Derivative liabilities, gross amount | 4 | 24
Derivatives designated as accounting hedges: | Foreign exchange and other contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 8,580 | 7,925
Derivative assets, gross amount | 0 | 264
Derivative liabilities, gross amount | 380 | 101
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 589 | 518
Derivative assets, gross amount | 0 | 0
Derivative liabilities, gross amount | 27 | 101
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Cash flow hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 2,609 | 2,549
Derivative assets, gross amount | 0 | 74
Derivative liabilities, gross amount | 68 | 0
Derivatives designated as accounting hedges: | Foreign exchange and other contracts | Net investment hedges |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 5,382 | 4,858
Derivative assets, gross amount | 0 | 190
Derivative liabilities, gross amount | 285 | 0
Derivatives not designated as accounting hedges: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 173,248 | 154,053
Derivative assets, gross amount | 2,152 | 1,842
Derivative liabilities, gross amount | 2,070 | 1,894
Derivatives not designated as accounting hedges: | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 168,561 | 149,890
Derivative assets, gross amount | 2,097 | 1,803
Derivative liabilities, gross amount | 2,054 | 1,880
Derivatives not designated as accounting hedges: | Interest rate contracts: | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 119,301 | 108,754
Derivative assets, gross amount | 847 | 865
Derivative liabilities, gross amount | 888 | 1,014
Derivatives not designated as accounting hedges: | Interest rate contracts: | Other interest rate exposures |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 1,243 | 909
Derivative assets, gross amount | 17 | 14
Derivative liabilities, gross amount | 10 | 9
Derivatives not designated as accounting hedges: | Foreign exchange and other contracts | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 6,450 | 6,951
Derivative assets, gross amount | 109 | 80
Derivative liabilities, gross amount | 121 | 52
Derivatives not designated as accounting hedges: | Commodity contracts | Customer accommodation: |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 42,810 | 34,185
Derivative assets, gross amount | 1,141 | 858
Derivative liabilities, gross amount | 1,045 | 814
Derivatives not designated as accounting hedges: | Other contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional or Contractual Amount | 3,444 | 3,254
Derivative assets, gross amount | 38 | 25
Derivative liabilities, gross amount | $ 6 | $ 5

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