Deferred Policy Acquisition Costs and Value of Business Acquired (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	$ 288	$ 122	$ 288	$ 536
Deferrals of commissions and expenses		55	56	43
Amortization, excluding unlocking		(94)	(84)	(72)
Unlocking (1)		6	(5)	2
Interest accrued		35	35	35
Amortization:
Net amortization included in the Consolidated Statements of Operations		(53)	(54)	(35)
Change in unrealized capital gains/losses on available-for-sale securities	(256)	146	(170)
Ending balance		270	122	288
Movement Analysis Of Value of Business Acquired VOBA [Roll Forward]
Beginning balance	305	40	305	551
Deferrals of commissions and expenses		4	3	6
Amortization, excluding unlocking		(86)	(76)	(66)
Unlocking (1)		17	(94)	(2)
Interest accrued		25	32	38
Net amortization included in the Consolidated Statements of Operations		(44)	(138)	(30)
Change in unrealized capital gains/losses on available-for-sale securities	(222)	139	(130)
Ending balance		139	40	305
Movement Analysis of Deferred Policy Acquisition Costs and Value of Business Acquired (VOBA) [Roll Forward]
Beginning balance	593	162	593	1,087
Deferrals of commissions and expenses		59	59	49
Amortization, excluding unlocking		(180)	(160)	(138)
Unlocking (1)		23	(99)	0
Interest accrued		60	67	73
Net amortization included in the Consolidated Statements of Operations		(97)	(192)	(65)
Change in unrealized capital gains/losses on available-for-sale securities	(478)	285	(300)
Ending balance		409	162	593
Estimated amount of VOBA amortization expense, net of interest:
2020		27
2021		22
2022		17
2023		15
2024		$ 12
Cumulative Effect, Period of Adoption, Adjustment
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	2		2
Amortization:
Ending balance				2
Movement Analysis Of Value of Business Acquired VOBA [Roll Forward]
Beginning balance	0		0
Ending balance				0
Movement Analysis of Deferred Policy Acquisition Costs and Value of Business Acquired (VOBA) [Roll Forward]
Beginning balance	$ 2		$ 2
Ending balance				$ 2
Minimum
Deferred Policy Acquisition Cost and Value of Business Acquired [Line Items]
Interest Accrual Rate Associated with Amortization Method of Present Value of Future Insurance Profits		5.50%
Maximum
Deferred Policy Acquisition Cost and Value of Business Acquired [Line Items]
Interest Accrual Rate Associated with Amortization Method of Present Value of Future Insurance Profits		7.00%