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Derivatives and Hedging Activities - Pre-Tax Net Gains (Losses) on Derivatives Not Designated as Hedging Instruments (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | $ 59 | $ 47 | $ 56
Interest rate |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 57 | 35 | 41
Foreign exchange |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 49 | 50 | 50
Commodity |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 7 | 12 | 22
Credit |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | (47) | (57) | (50)
Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | (7) | 7 | (7)
Corporate services income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 107 | 98 | 115
Corporate services income | Interest rate |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 51 | 35 | 41
Corporate services income | Foreign exchange |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 49 | 50 | 50
Corporate services income | Commodity |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 7 | 12 | 22
Corporate services income | Credit |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 1 | 2
Corporate services income | Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 0 | 0
Consumer mortgage income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 2 | (1)
Consumer mortgage income | Interest rate |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 0 | 0
Consumer mortgage income | Foreign exchange |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 0 | 0
Consumer mortgage income | Commodity |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 0 | 0
Consumer mortgage income | Credit |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 0 | 0
Consumer mortgage income | Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 2 | (1)
Other income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | (48) | (53) | (58)
Other income | Interest rate |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 6 | 0 | 0
Other income | Foreign exchange |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 0 | 0
Other income | Commodity |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | 0 | 0 | 0
Other income | Credit |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | (47) | (58) | (52)
Other income | Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net gains (losses) | $ (7) | $ 5 | $ (6)

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