Investments - Fair Value and Gross Unrealized Losses in a Continuous Unrealized Loss Position (Details) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($) security	Dec. 31, 2023 USD ($) security
Fair Value
Less Than or Equal to Twelve Months	$ 31,284	$ 17,427
Greater Than Twelve Months	32,529	44,508
Total	63,813	61,935
Gross Unrealized Losses
Less Than or Equal to Twelve Months	4,449	3,526
Greater Than Twelve Months	3,820	6,241
Total	$ 8,269	$ 9,767
Total number of fixed maturity AFS securities in an unrealized loss position | security	6,458	7,605
Unrealized holding gains (losses) arising during the period	$ (15)	$ (8)
Corporate bonds
Fair Value
Less Than or Equal to Twelve Months	26,120	14,005
Greater Than Twelve Months	26,231	34,595
Total	52,351	48,600
Gross Unrealized Losses
Less Than or Equal to Twelve Months	3,992	3,270
Greater Than Twelve Months	3,229	5,002
Total	7,221	8,272
U.S. government bonds
Fair Value
Less Than or Equal to Twelve Months	38	65
Greater Than Twelve Months	223	195
Total	261	260
Gross Unrealized Losses
Less Than or Equal to Twelve Months	2	6
Greater Than Twelve Months	23	23
Total	25	29
State and municipal bonds
Fair Value
Less Than or Equal to Twelve Months	985	371
Greater Than Twelve Months	709	874
Total	1,694	1,245
Gross Unrealized Losses
Less Than or Equal to Twelve Months	192	72
Greater Than Twelve Months	141	345
Total	333	417
Foreign government bonds
Fair Value
Less Than or Equal to Twelve Months	49	111
Greater Than Twelve Months	100	57
Total	149	168
Gross Unrealized Losses
Less Than or Equal to Twelve Months	18	31
Greater Than Twelve Months	29	16
Total	47	47
RMBS
Fair Value
Less Than or Equal to Twelve Months	472	360
Greater Than Twelve Months	764	886
Total	1,236	1,246
Gross Unrealized Losses
Less Than or Equal to Twelve Months	57	20
Greater Than Twelve Months	99	177
Total	156	197
CMBS
Fair Value
Less Than or Equal to Twelve Months	731	583
Greater Than Twelve Months	515	589
Total	1,246	1,172
Gross Unrealized Losses
Less Than or Equal to Twelve Months	66	56
Greater Than Twelve Months	69	147
Total	135	203
ABS
Fair Value
Less Than or Equal to Twelve Months	2,871	1,900
Greater Than Twelve Months	3,898	7,217
Total	6,769	9,117
Gross Unrealized Losses
Less Than or Equal to Twelve Months	119	68
Greater Than Twelve Months	221	517
Total	340	585
Hybrid and redeemable preferred securities
Fair Value
Less Than or Equal to Twelve Months	18	32
Greater Than Twelve Months	89	95
Total	107	127
Gross Unrealized Losses
Less Than or Equal to Twelve Months	3	3
Greater Than Twelve Months	9	14
Total	$ 12	$ 17