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	$ 20,745	$ 16,851
Greater Than Twelve Months	31,552	43,082
Total	52,297	59,933
Gross Unrealized Losses
Less Than or Equal to Twelve Months	2,100	1,999
Greater Than Twelve Months	3,658	4,967
Total	$ 5,758	$ 6,966
Total number of fixed maturity AFS securities in an unrealized loss position | security	6,060	7,167
Unrealized holding losses arising during the period	$ 15	$ 7
Corporate bonds
Fair Value
Less Than or Equal to Twelve Months	16,496	13,439
Greater Than Twelve Months	25,346	33,285
Total	41,842	46,724
Gross Unrealized Losses
Less Than or Equal to Twelve Months	1,841	1,744
Greater Than Twelve Months	3,086	4,013
Total	4,927	5,757
U.S. government bonds
Fair Value
Less Than or Equal to Twelve Months	26	65
Greater Than Twelve Months	223	194
Total	249	259
Gross Unrealized Losses
Less Than or Equal to Twelve Months	2	6
Greater Than Twelve Months	23	22
Total	25	28
State and municipal bonds
Fair Value
Less Than or Equal to Twelve Months	493	371
Greater Than Twelve Months	658	814
Total	1,151	1,185
Gross Unrealized Losses
Less Than or Equal to Twelve Months	63	72
Greater Than Twelve Months	133	158
Total	196	230
Foreign government bonds
Fair Value
Less Than or Equal to Twelve Months	45	108
Greater Than Twelve Months	100	57
Total	145	165
Gross Unrealized Losses
Less Than or Equal to Twelve Months	17	31
Greater Than Twelve Months	29	15
Total	46	46
RMBS
Fair Value
Less Than or Equal to Twelve Months	290	355
Greater Than Twelve Months	724	840
Total	1,014	1,195
Gross Unrealized Losses
Less Than or Equal to Twelve Months	18	20
Greater Than Twelve Months	89	118
Total	107	138
CMBS
Fair Value
Less Than or Equal to Twelve Months	619	583
Greater Than Twelve Months	515	586
Total	1,134	1,169
Gross Unrealized Losses
Less Than or Equal to Twelve Months	48	56
Greater Than Twelve Months	68	125
Total	116	181
ABS
Fair Value
Less Than or Equal to Twelve Months	2,763	1,898
Greater Than Twelve Months	3,897	7,212
Total	6,660	9,110
Gross Unrealized Losses
Less Than or Equal to Twelve Months	110	68
Greater Than Twelve Months	221	503
Total	331	571
Hybrid and redeemable preferred securities
Fair Value
Less Than or Equal to Twelve Months	13	32
Greater Than Twelve Months	89	94
Total	102	126
Gross Unrealized Losses
Less Than or Equal to Twelve Months	1	2
Greater Than Twelve Months	9	13
Total	$ 10	$ 15