Income Taxes (Details) - Effective Tax Rate - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
U.S. income before income taxes	$ 4,107	$ 3,095	$ 3,211
Foreign income (loss) before income taxes	351	142	(73)
Income before income taxes	$ 4,458	$ 3,237	$ 3,138
Statutory tax rate (percent)	21.00%	21.00%	21.00%
Expected federal income tax expense	$ 936	$ 680	$ 659
Tax effect of nontaxable investment income	(147)	(147)	(149)
Tax effect of other, net	7	7	6
Total income tax expense included in the consolidated statement of income	$ 796	$ 540	$ 516
Effective tax rate (percent)	18.00%	17.00%	16.00%
Income taxes paid	$ 707	$ 578	$ 428
Current income tax payable	$ 119	$ 131

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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