Investments (Continuous Gross Unrealized Losses for Fixed Maturity Securities by Sector) (Details) $ in Millions	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	$ 9,645	$ 20,825
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	$ 726	$ 1,460
Fixed maturity securities in continuous unrealized loss position, less than 12 months, number of securities	1,573	3,356
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	$ 37,417	$ 36,595
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 5,120	$ 6,388
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, number of securities	5,038	5,195
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	$ 4,041	$ 10,758
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	330	719
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	19,133	17,329
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	2,639	3,146
Foreign corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	1,460	3,269
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	201	351
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	5,485	5,502
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	813	1,117
RMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	995	1,227
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	66	82
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	4,308	4,624
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	554	785
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	1,305	2,384
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	51	116
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,556	1,858
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	530	575
ABS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	482	717
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	2	10
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	769	1,076
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	53	65
CMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	841	1,326
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	30	90
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	4,043	4,338
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	216	325
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	395	871
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	30	63
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,632	1,435
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	264	304
Foreign government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	126	273
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	16	29
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	491	433
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 51	$ 71