Investments - Available-for-sale Securities in Gross Unrealized Loss Position (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Gross Unrealized Losses [Abstract]
Total, Estimated Fair Value	$ 29,944	$ 6,065
Total, Gross Unrealized Losses	4,583	112
Fixed maturity securities
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	28,394	5,695
Less than 12 Months, Gross Unrealized Losses	4,152	92
12 Months or Longer, Estimated Fair Value	1,550	370
12 Months or Longer, Gross Unrealized Losses	431	20
Total, Estimated Fair Value	29,944	6,065
Total, Gross Unrealized Losses	4,583	112
Corporate and Other Bonds
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	16,707	2,389
Less than 12 Months, Gross Unrealized Losses	2,117	48
12 Months or Longer, Estimated Fair Value	914	136
12 Months or Longer, Gross Unrealized Losses	281	8
Total, Estimated Fair Value	17,621	2,525
Total, Gross Unrealized Losses	2,398	56
States, municipalities and political subdivisions
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	4,793	730
Less than 12 Months, Gross Unrealized Losses	1,029	14
12 Months or Longer, Estimated Fair Value	128
12 Months or Longer, Gross Unrealized Losses	51
Total, Estimated Fair Value	4,921	730
Total, Gross Unrealized Losses	1,080	14
Residential mortgage-backed
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	2,582	1,043
Less than 12 Months, Gross Unrealized Losses	462	8
12 Months or Longer, Estimated Fair Value	17
12 Months or Longer, Gross Unrealized Losses	8
Total, Estimated Fair Value	2,599	1,043
Total, Gross Unrealized Losses	470	8
Commercial mortgage-backed
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	1,372	527
Less than 12 Months, Gross Unrealized Losses	194	7
12 Months or Longer, Estimated Fair Value	233	167
12 Months or Longer, Gross Unrealized Losses	43	12
Total, Estimated Fair Value	1,605	694
Total, Gross Unrealized Losses	237	19
Other asset-backed
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	2,433	840
Less than 12 Months, Gross Unrealized Losses	307	10
12 Months or Longer, Estimated Fair Value	233	62
12 Months or Longer, Gross Unrealized Losses	42
Total, Estimated Fair Value	2,666	902
Total, Gross Unrealized Losses	349	10
Total asset-backed
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	6,387	2,410
Less than 12 Months, Gross Unrealized Losses	963	25
12 Months or Longer, Estimated Fair Value	483	229
12 Months or Longer, Gross Unrealized Losses	93	12
Total, Estimated Fair Value	6,870	2,639
Total, Gross Unrealized Losses	1,056	37
U.S. Treasury and obligations of government-sponsored enterprises
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	61	69
Less than 12 Months, Gross Unrealized Losses	1	3
12 Months or Longer, Estimated Fair Value		5
12 Months or Longer, Gross Unrealized Losses
Total, Estimated Fair Value	61	74
Total, Gross Unrealized Losses	1	3
Foreign government
Gross Unrealized Losses [Abstract]
Less than 12 Months, Estimated Fair Value	446	97
Less than 12 Months, Gross Unrealized Losses	42	2
12 Months or Longer, Estimated Fair Value	25
12 Months or Longer, Gross Unrealized Losses	6
Total, Estimated Fair Value	471	97
Total, Gross Unrealized Losses	$ 48	$ 2