Investments (Amortized Cost and Fair Value of Fixed Maturity Holdings by Industry Type) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 57,608	$ 55,873
Fixed maturity securities, available-for-sale	53,294	60,749
Corporate Debt Securities [Member]
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 37,819	$ 35,239
% of Total	100.00%	100.00%
Fixed maturity securities, available-for-sale	$ 34,374	$ 38,103
Corporate Debt Securities [Member] | Financial Services Sector [Member]
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 14,008	$ 13,101
% of Total	37.00%	36.90%
Fixed maturity securities, available-for-sale	$ 12,703	$ 14,045
Corporate Debt Securities [Member] | Commercial and Industrial Sector [Member]
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 19,152	$ 17,857
% of Total	51.00%	50.80%
Fixed maturity securities, available-for-sale	$ 17,526	$ 19,375
Corporate Debt Securities [Member] | Utility Sector [Member]
Corporate Securities by Investment Sector And Credit Rating [Line Items]
Amortized Cost	$ 4,659	$ 4,281
% of Total	12.00%	12.30%
Fixed maturity securities, available-for-sale	$ 4,145	$ 4,683