Investments (Amortized Cost and Fair Value of Fixed Maturity Holdings by Industry Type) (Details) - USD ($) $ in Millions	Jun. 30, 2025		Dec. 31, 2024
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 91,888		$ 82,907
Fixed maturity securities, available-for-sale	86,043	[1]	77,617	[2]
Corporate Debt Securities [Member]
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	61,006		54,705
Fixed maturity securities, available-for-sale	$ 57,326	[1]	$ 50,991	[2]
Percentage Of Total Corporate Fixed Maturity Security	100.00%		100.00%
Corporate Debt Securities [Member] | Finance
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 18,947		$ 17,905
Fixed maturity securities, available-for-sale	$ 17,800		$ 16,673
Percentage Of Total Corporate Fixed Maturity Security	31.10%		32.70%
Corporate Debt Securities [Member] | Industrial
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 31,866		$ 28,267
Fixed maturity securities, available-for-sale	$ 30,046		$ 26,476
Percentage Of Total Corporate Fixed Maturity Security	52.40%		51.90%
Corporate Debt Securities [Member] | Utility
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 10,193		$ 8,533
Fixed maturity securities, available-for-sale	$ 9,480		$ 7,842
Percentage Of Total Corporate Fixed Maturity Security	16.50%		15.40%

[1] Excludes limited partnerships that are measured at estimated fair value using the NAV per share (or its equivalent) as a practical expedient. As of June 30, 2025, the fair value of such investments was $954 million.

[2] Excludes limited partnerships that are measured at estimated fair value using the NAV per share (or its equivalent) as a practical expedient. As of December 31, 2024, the fair value of such investments was $966 million