v3.26.1
Derivative Instruments (Exposure from Credit Derivatives by Rating of the Underlying Credits) (Details) - USD ($)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Credit Derivatives [Line Items]    
Credit Derivative Current Fair Value [1] $ 1 $ (7)
Maximum Potential Future Exposure on Credit Risk Derivatives [1],[2] $ 8,048 $ 6,573
Derivative Average Remaining Maturity [1],[3] 5 years 9 months 18 days 6 years
Standard Poors AAA To A Minus Ratings [Member] | Single Name Credit Default Swaps [Member]    
Credit Derivatives [Line Items]    
Credit Derivative Current Fair Value [1] $ 2 $ (7)
Maximum Potential Future Exposure on Credit Risk Derivatives [1],[2] $ 471 $ 490
Derivative Average Remaining Maturity [1],[3] 14 years 2 months 12 days 14 years 2 months 12 days
Standard Poors BBB Rating [Member] | Single Name Credit Default Swaps [Member]    
Credit Derivatives [Line Items]    
Credit Derivative Current Fair Value [1] $ 2 $ 2
Maximum Potential Future Exposure on Credit Risk Derivatives [1],[2] $ 174 $ 170
Derivative Average Remaining Maturity [1],[3] 1 year 7 months 6 days 2 years 1 month 6 days
Standard Poors BBB Rating [Member] | Credit Default Swaps Referencing Indices [Member]    
Credit Derivatives [Line Items]    
Credit Derivative Current Fair Value [1] $ (3) $ (2)
Maximum Potential Future Exposure on Credit Risk Derivatives [1],[2] $ 7,403 $ 5,903
Derivative Average Remaining Maturity [1],[3] 5 years 4 months 24 days 5 years 6 months
Standard Poors BBB Rating [Member] | Credit Default Subtotal [Member]    
Credit Derivatives [Line Items]    
Credit Derivative Current Fair Value [1] $ (1) $ 0
Maximum Potential Future Exposure on Credit Risk Derivatives [1],[2] $ 7,577 $ 6,073
Derivative Average Remaining Maturity [1],[3] 5 years 3 months 18 days 5 years 4 months 24 days
Standard & Poor's, BB Rating [Member]    
Credit Derivatives [Line Items]    
Derivative Average Remaining Maturity [1],[2] 0 years 6 months
Standard & Poor's, BB Rating [Member] | Single Name Credit Default Swaps [Member]    
Credit Derivatives [Line Items]    
Credit Derivative Current Fair Value [1] $ 0 $ 0
Maximum Potential Future Exposure on Credit Risk Derivatives [1],[2] $ 0 $ 5
Standard & Poor's, B Rating    
Credit Derivatives [Line Items]    
Derivative Average Remaining Maturity [3] 0 years 6 months
Standard & Poor's, B Rating | Single Name Credit Default Swaps [Member]    
Credit Derivatives [Line Items]    
Credit Derivative Current Fair Value [1] $ 0 $ 0
Maximum Potential Future Exposure on Credit Risk Derivatives [2] $ 0 $ 5
[1] ating agency designations are based on ratings from Standard and Poor’s (“S&P”) when available. Other credited rating agencies or internal ratings may be used when S&P ratings are not available.
[2] Assumes the value of the referenced credit obligations is zero.
[3] The weighted average years to maturity of the credit default swaps is calculated based on weighted average notional amounts.