Investments (Continuous Gross Unrealized Losses for Fixed Maturity Securities by Sector) (Details) $ in Millions	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	$ 51,788	$ 16,729
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	$ 6,538	$ 305
Fixed maturity securities in continuous unrealized loss position, less than 12 months, number of securities	7,261	2,423
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	$ 11,815	$ 1,658
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 2,836	$ 145
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, number of securities	2,018	368
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	$ 24,163	$ 5,051
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	3,279	111
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	3,915	887
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	1,157	76
Foreign corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	8,219	2,016
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	1,407	60
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,560	305
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	505	43
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	3,037	1,712
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	259	40
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,146	222
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	337	20
RMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	4,693	3,481
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	489	50
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	2,245	32
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	447	1
CMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	5,524	1,390
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	534	21
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	961	95
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	165	3
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	2,026	347
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	313	6
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	239	6
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	81	0
ABS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	3,347	2,454
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	159	13
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	1,728	93
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	136	1
Foreign government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities in continuous unrealized loss position, less than 12 months, estimated fair value	779	278
Fixed maturity securities in continuous unrealized loss position, less than 12 months, gross unrealized losses	98	4
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, estimated fair value	21	18
Fixed maturity securities in continuous unrealized loss position, 12 months or greater, gross unrealized losses	$ 8	$ 1

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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