v3.26.3
Derivative Instruments (Fair Value Hedge Attributable to Foreign Currency) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Interest Rate Contract | Income Statement Location [Axis]: us-gaap:BenefitsLossesAndExpenses        
Derivative Instruments, Gain (Loss) [Line Items]        
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments $ 0 $ 0 $ 0 $ 0
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge 0 0 0 0
Interest Rate Contract | Income Statement Location [Axis]: us-gaap:InterestCreditedToPolicyholdersAccountBalances        
Derivative Instruments, Gain (Loss) [Line Items]        
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments (85) 1 (110) 23
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge 83 (1) 110 (27)
Financial Futures | Income Statement Location [Axis]: us-gaap:BenefitsLossesAndExpenses        
Derivative Instruments, Gain (Loss) [Line Items]        
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments (33) 0 (43) 14
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge 33 (1) 44 (15)
Financial Futures | Income Statement Location [Axis]: us-gaap:InterestCreditedToPolicyholdersAccountBalances        
Derivative Instruments, Gain (Loss) [Line Items]        
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments 0 0 0 0
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge $ 0 $ 0 $ 0 $ 0