v3.26.1
Financial Derivatives (Impact of Fair Value Hedge Accounting on the Carrying Value of Hedged Items) (Details) - Fair value hedges - Designated as Hedging Instruments under GAAP - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Borrowed Funds    
Derivative Instruments, Gain (Loss) [Line Items]    
Carrying Value of the Hedged Items $ 39,534 $ 39,945
Cumulative Fair Value Hedge Adjustment included in the Carrying Value of Hedged Items (301) (101)
Deposits    
Derivative Instruments, Gain (Loss) [Line Items]    
Carrying Value of the Hedged Items 200 100
Cumulative Fair Value Hedge Adjustment included in the Carrying Value of Hedged Items 0 0
Securities available-for-sale    
Derivative Instruments, Gain (Loss) [Line Items]    
Carrying Value of the Hedged Items 19,096 22,651
Cumulative Fair Value Hedge Adjustment included in the Carrying Value of Hedged Items $ (19) $ 174