Investments (Continuous Gross Unrealized Losses for Fixed Maturity Securities by Sector) (Details) $ in Millions	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	$ 10,055	$ 7,973
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	$ 774	$ 585
Fixed maturity securities in continuous unrealized loss position, less than 12 months, number of securities	2,135	1,339
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	$ 40,581	$ 51,190
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 4,912	$ 6,462
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, number of securities	5,423	6,958
U.S. corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	$ 6,005	$ 4,549
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	467	409
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	18,501	22,435
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	2,318	2,923
Foreign corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	1,678	1,010
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	166	74
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	6,199	8,229
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	884	1,202
U.S. government and agency
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	298	445
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	23	8
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	2,238	3,453
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	447	509
RMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	552	413
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	35	21
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	5,207	5,749
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	599	784
ABS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	407	572
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	6	3
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,203	3,355
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	59	128
CMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	648	411
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	47	33
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	5,123	5,713
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	312	568
State and political subdivision
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	331	460
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	21	31
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,591	1,636
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	231	267
Foreign government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	136	113
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	9	6
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	519	620
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 62	$ 81