Investments - Available-for-Sale Securities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	$ 40,788	$ 41,561
Debt Securities, Available-for-sale, Allowance for Credit Loss	(1)	(23)	$ 0
Gross Unrealized Gains, fixed maturities, available-for-sale	2,204	3,560
Gross Unrealized Losses, fixed maturities, available-for-sale	(144)	(63)
Total fixed maturities	42,847	45,035
Amortized Cost
One year or less	1,400	1,411
Over one year through five years	8,615	7,832
Over five years through ten years	8,303	7,622
Over ten years	10,761	12,206
Subtotal	29,079	29,071
Mortgage-backed and asset-backed securities	11,709	12,490
Fair Value
One year or less	1,419	1,432
Over one year through five years	8,894	8,286
Over five years through ten years	8,633	8,354
Over ten years	11,979	14,028
Subtotal	30,925	32,100
Mortgage-backed and asset-backed securities	11,922	12,935
ABS
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	1,125	1,525
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Gross Unrealized Gains, fixed maturities, available-for-sale	13	39
Gross Unrealized Losses, fixed maturities, available-for-sale	(3)	0
Total fixed maturities	1,135	1,564
CLOs
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	3,019	2,780
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Gross Unrealized Gains, fixed maturities, available-for-sale	8	7
Gross Unrealized Losses, fixed maturities, available-for-sale	(2)	(7)
Total fixed maturities	3,025	2,780
CMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	3,955	4,219
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Gross Unrealized Gains, fixed maturities, available-for-sale	179	286
Gross Unrealized Losses, fixed maturities, available-for-sale	(15)	(21)
Total fixed maturities	4,119	4,484
Corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	17,744	18,401
Debt Securities, Available-for-sale, Allowance for Credit Loss	(1)	(23)	0
Gross Unrealized Gains, fixed maturities, available-for-sale	1,038	1,926
Gross Unrealized Losses, fixed maturities, available-for-sale	(74)	(31)
Total fixed maturities	18,707	20,273
Foreign government/government agencies
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	883	842
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Gross Unrealized Gains, fixed maturities, available-for-sale	33	77
Gross Unrealized Losses, fixed maturities, available-for-sale	(6)	0
Total fixed maturities	910	919
Municipal
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	7,473	8,564
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0	$ 0
Gross Unrealized Gains, fixed maturities, available-for-sale	787	940
Gross Unrealized Losses, fixed maturities, available-for-sale	(3)	(1)
Total fixed maturities	8,257	9,503
Residential mortgage-backed securities ("RMBS")
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	3,610	3,966
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Gross Unrealized Gains, fixed maturities, available-for-sale	60	144
Gross Unrealized Losses, fixed maturities, available-for-sale	(27)	(3)
Total fixed maturities	3,643	4,107
U.S. Treasuries
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, available-for-sale, at fair value, amortized cost	2,979	1,264
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Gross Unrealized Gains, fixed maturities, available-for-sale	86	141
Gross Unrealized Losses, fixed maturities, available-for-sale	(14)	0
Total fixed maturities	$ 3,051	$ 1,405