v3.26.3
Derivative Instruments (Current Period Cash Flow Hedges in AOCI (loss) before Taxes) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Jun. 30, 2026
Dec. 31, 2025
Jun. 30, 2025
Dec. 31, 2024
Derivative Instruments, Gain (Loss) [Line Items]                
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) $ 42   $ 42     $ (6)    
Cash Flow Hedging [Member]                
Derivative Instruments, Gain (Loss) [Line Items]                
Derivative, Amount of Hedged Item (1,105) $ (572) (1,105) $ (572) $ (931) $ (748) $ (473) $ (495)
Cash Flow Derivatives Deferred In OCI 189 115 403 125        
Cash Flow Hedging [Member] | Income Statement Location [Axis]: us-gaap:InterestExpense                
Derivative Instruments, Gain (Loss) [Line Items]                
Cash Flow Derivative Gains Losses Reclassified Into Income From AOCI (1) (2) (4) (6)        
Cash Flow Hedging [Member] | Income Statement Location [Axis]: us-gaap:NetInvestmentIncome                
Derivative Instruments, Gain (Loss) [Line Items]                
Cash Flow Derivative Gains Losses Reclassified Into Income From AOCI $ (16) $ (18) $ (50) $ (54)