Derivatives (Credit Derivatives) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (196)	$ (228)
Maximum Amount of Future Payments under Credit Default Swaps	$ 11,764	$ 12,468
Weighted Average Years to Maturity	3 years 4 months 24 days	4 years 6 months
Aaa/Aa/A
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (73)	$ (82)
Maximum Amount of Future Payments under Credit Default Swaps	$ 4,198	$ 3,980
Weighted Average Years to Maturity	2 years 2 months 12 days	2 years 7 months 6 days
Aaa/Aa/A | Single name credit default swaps (3)
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (1)	$ (2)
Maximum Amount of Future Payments under Credit Default Swaps	$ 72	$ 150
Weighted Average Years to Maturity	1 year 10 months 24 days	1 year 7 months 6 days
Aaa/Aa/A | Credit default swaps referencing indices
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (72)	$ (80)
Maximum Amount of Future Payments under Credit Default Swaps	$ 4,126	$ 3,830
Weighted Average Years to Maturity	2 years 2 months 12 days	2 years 8 months 12 days
Baa
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (112)	$ (146)
Maximum Amount of Future Payments under Credit Default Swaps	$ 7,365	$ 8,287
Weighted Average Years to Maturity	4 years 1 month 6 days	5 years 3 months 18 days
Baa | Single name credit default swaps (3)
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (1)	$ (1)
Maximum Amount of Future Payments under Credit Default Swaps	$ 102	$ 99
Weighted Average Years to Maturity	1 year 7 months 6 days	2 years 1 month 6 days
Baa | Credit default swaps referencing indices
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (111)	$ (145)
Maximum Amount of Future Payments under Credit Default Swaps	$ 7,263	$ 8,188
Weighted Average Years to Maturity	4 years 1 month 6 days	5 years 4 months 24 days
Ba
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (2)	$ (2)
Maximum Amount of Future Payments under Credit Default Swaps	$ 42	$ 42
Weighted Average Years to Maturity	1 year 7 months 6 days	2 years 7 months 6 days
Ba | Single name credit default swaps (3)
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ 0	$ 0
Maximum Amount of Future Payments under Credit Default Swaps	$ 17	$ 17
Weighted Average Years to Maturity	1 year 1 month 6 days	2 years 1 month 6 days
Ba | Credit default swaps referencing indices
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (2)	$ (2)
Maximum Amount of Future Payments under Credit Default Swaps	$ 25	$ 25
Weighted Average Years to Maturity	2 years	3 years
B [Member]
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (10)	$ (2)
Maximum Amount of Future Payments under Credit Default Swaps	$ 144	$ 129
Weighted Average Years to Maturity	3 years 8 months 12 days	5 years
B [Member] | Credit default swaps referencing indices
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (10)	$ (2)
Maximum Amount of Future Payments under Credit Default Swaps	$ 144	$ 129
Weighted Average Years to Maturity	3 years 8 months 12 days	5 years
Caa
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (1)	$ (4)
Maximum Amount of Future Payments under Credit Default Swaps	$ 15
Weighted Average Years to Maturity	2 years	2 years 6 months
Caa | Credit default swaps referencing indices
Credit Derivatives [Line Items]
Estimated Fair Value of Credit Default Swaps	$ (1)	$ (4)
Maximum Amount of Future Payments under Credit Default Swaps	$ 15	$ 30
Weighted Average Years to Maturity	2 years	2 years 6 months