Investments (Details) - Concentrations and Credit Quality - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Investment disclosure details
Fixed maturities, at fair value	$ 83,666	$ 77,807
Below investment grade [Member]
Investment disclosure details
Fixed maturities, at fair value	980	982
U.S. Treasury securities and obligations of U.S. government and government agencies and authorities [Member]
Investment disclosure details
Fixed maturities, at fair value	$ 5,570	$ 6,368
Credit Concentration Risk [Member] | Shareholders' equity, total [Member] | U.S. Treasury securities and obligations of U.S. government and government agencies and authorities [Member] | Minimum [Member]
Investment disclosure details
Concentration risk as a percentage of shareholders' equity	5.00%	5.00%