Investments (Fixed Maturity Securities by Sector) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	$ 80,247	$ 78,287
Fixed maturity securities, allowance for credit losses	11	11
Fixed maturity securities, gross unrealized gains	3,863	8,701
Fixed maturity securities, gross unrealized losses	2,597	450
Fixed maturity securities, estimated fair value	81,502	86,527
U.S. corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	35,220	34,773
Fixed maturity securities, allowance for credit losses	2	2
Fixed maturity securities, gross unrealized gains	1,434	3,890
Fixed maturity securities, gross unrealized losses	1,201	187
Fixed maturity securities, estimated fair value	35,451	38,474
Foreign corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	11,172	10,813
Fixed maturity securities, allowance for credit losses	7	7
Fixed maturity securities, gross unrealized gains	276	902
Fixed maturity securities, gross unrealized losses	494	103
Fixed maturity securities, estimated fair value	10,947	11,605
RMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	8,782	8,838
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	185	433
Fixed maturity securities, gross unrealized losses	275	51
Fixed maturity securities, estimated fair value	8,692	9,220
U.S. government and agency
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	8,344	7,188
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	1,342	2,040
Fixed maturity securities, gross unrealized losses	223	60
Fixed maturity securities, estimated fair value	9,463	9,168
CMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	7,023	6,890
Fixed maturity securities, allowance for credit losses	2	0
Fixed maturity securities, gross unrealized gains	46	329
Fixed maturity securities, gross unrealized losses	173	24
Fixed maturity securities, estimated fair value	6,894	7,193
State and political subdivision
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	3,885	3,937
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	456	829
Fixed maturity securities, gross unrealized losses	101	6
Fixed maturity securities, estimated fair value	4,240	4,760
ABS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	4,594	4,255
Fixed maturity securities, allowance for credit losses	0	2
Fixed maturity securities, gross unrealized gains	8	34
Fixed maturity securities, gross unrealized losses	98	14
Fixed maturity securities, estimated fair value	4,504	4,275
Foreign government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	1,227	1,593
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	116	244
Fixed maturity securities, gross unrealized losses	32	5
Fixed maturity securities, estimated fair value	$ 1,311	$ 1,832

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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