Investments (Amortized Cost and Fair Value of Fixed Maturity Holdings by Industry Type) (Details) - USD ($) $ in Millions	Jun. 30, 2023		Dec. 31, 2022
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 62,185		$ 59,663
Fixed maturity securities, available-for-sale	56,236	[1]	52,901	[2]
Corporate Debt Securities [Member]
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	40,751		38,963
Fixed maturity securities, available-for-sale	$ 36,178	[1]	$ 33,969	[2]
% of Total	100.00%		100.00%
Corporate Debt Securities [Member] | Finance
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 14,948		$ 14,551
Fixed maturity securities, available-for-sale	$ 13,120		$ 12,680
% of Total	36.30%		37.30%
Corporate Debt Securities [Member] | Industrial
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 20,574		$ 19,624
Fixed maturity securities, available-for-sale	$ 18,548		$ 17,257
% of Total	51.20%		50.80%
Corporate Debt Securities [Member] | Utility
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 5,229		$ 4,788
Fixed maturity securities, available-for-sale	$ 4,510		$ 4,032
% of Total	12.50%		11.90%

[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, 2023, the fair value of such investments was $768 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, 2022, the fair value of such investments was $683 million