v3.26.1
Derivative Instruments Derivative Instruments (Fair Value Hedge Attributable to Foreign Currency) (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Derivative Instruments, Gain (Loss) [Line Items]      
Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) $ (8)   $ (6)
Interest Rate Contract      
Derivative Instruments, Gain (Loss) [Line Items]      
Fair Value Hedge Liabilities (1,468)   (1,463)
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease) [1] 4   5
Interest Rate Contract | Income Statement Location [Axis]: us-gaap:BenefitsLossesAndExpenses      
Derivative Instruments and Hedging Activities Disclosure [Abstract]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments 0 $ 0  
Derivative Instruments, Gain (Loss) [Line Items]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments 0 0  
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge 0 0  
Interest Rate Contract | Income Statement Location [Axis]: us-gaap:InterestExpenseBorrowings      
Derivative Instruments and Hedging Activities Disclosure [Abstract]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments (8) 20  
Derivative Instruments, Gain (Loss) [Line Items]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments (8) 20  
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge 9 (25)  
Financial Futures | Income Statement Location [Axis]: us-gaap:BenefitsLossesAndExpenses      
Derivative Instruments and Hedging Activities Disclosure [Abstract]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments (2) 13  
Derivative Instruments, Gain (Loss) [Line Items]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments (2) 13  
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge 4 (13)  
Financial Futures | Income Statement Location [Axis]: us-gaap:InterestExpenseBorrowings      
Derivative Instruments and Hedging Activities Disclosure [Abstract]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments 0 0  
Derivative Instruments, Gain (Loss) [Line Items]      
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments 0 0  
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge 0 $ 0  
Other Contract      
Derivative Instruments, Gain (Loss) [Line Items]      
Fair Value Hedge Liabilities (585)   (547)
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease) [1] $ 3   $ 1
[1] Includes $(8) million and $(6) million of cumulative adjustment on discontinued fair value hedging relationships at March 31, 2026 and December 31, 2025, respectively.