v3.26.3
Derivative Instruments (Cash Flow Hedges) (Details) - Cash Flow Hedging [Member] - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Derivative Instruments, Gain (Loss) [Line Items]        
Cash Flow Derivatives Deferred In OCI $ 189 $ 115 $ 403 $ 125
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)
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)
Interest Rate Swaps        
Derivative Instruments, Gain (Loss) [Line Items]        
Cash Flow Derivatives Deferred In OCI (286) 12 (360) (40)
Interest Rate Swaps | 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)
Interest Rate Swaps | Income Statement Location [Axis]: us-gaap:NetInvestmentIncome        
Derivative Instruments, Gain (Loss) [Line Items]        
Cash Flow Derivative Gains Losses Reclassified Into Income From AOCI 0 (1) 0 (3)
Currency Swap [Member]        
Derivative Instruments, Gain (Loss) [Line Items]        
Cash Flow Derivatives Deferred In OCI (97) 127 43 85
Currency Swap [Member] | Income Statement Location [Axis]: us-gaap:InterestExpense        
Derivative Instruments, Gain (Loss) [Line Items]        
Cash Flow Derivative Gains Losses Reclassified Into Income From AOCI 0 0 0 0
Currency Swap [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) $ (17) $ (50) $ (51)