Deferred Policy Acquisition Costs and Value of Business Acquired - Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance			$ 288	$ 536
Deferrals of commissions and expenses			41	29
Amortization:
Amortization, excluding unlocking			(64)	(52)
Unlocking			(17)	5
Interest accrued			26	26
Net amortization included in the Condensed Consolidated Statements of Operations			(55)	(21)
Change due to unrealized capital gains/losses on available-for-sale securities			(142)	(274)
Ending balance	$ 134	$ 270	134	270
Movement Analysis Of Value of Business Acquired VOBA [Roll Forward]
Beginning balance			305	551
Deferrals of commissions and expenses			1	4
Amortization, excluding unlocking			(52)	(50)
Unlocking			(121)	2
Interest accrued			25	29
Net amortization included in the Condensed Consolidated Statements of Operations			(148)	(19)
Change due to unrealized capital gains/losses on available-for-sale securities			(142)	(246)
Ending balance	16	290	16	290
Movement Analysis of Deferred Policy Acquisition Costs and Value of Business Acquired (VOBA) [Roll Forward]
Beginning balance			593	1,087
Deferrals of commissions and expenses			42	33
Amortization, excluding unlocking			(116)	(102)
Unlocking			(138)	7
Interest accrued			51	55
Net amortization included in the Condensed Consolidated Statements of Operations	(160)	(31)	(203)	(40)
Change due to unrealized capital gains/losses on available-for-sale securities			(284)	(520)
Ending balance	$ 150	$ 560	$ 150	$ 560
Minimum
Movement Analysis of Deferred Policy Acquisition Costs and Value of Business Acquired (VOBA) [Roll Forward]
Value of Business Acquired (VOBA), Interest accrued percentage			5.50%	5.50%
Maximum
Movement Analysis of Deferred Policy Acquisition Costs and Value of Business Acquired (VOBA) [Roll Forward]
Value of Business Acquired (VOBA), Interest accrued percentage			7.00%	7.00%
Accounting Standards Update 2016-13
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance			$ 2
Movement Analysis Of Value of Business Acquired VOBA [Roll Forward]
Beginning balance			0
Movement Analysis of Deferred Policy Acquisition Costs and Value of Business Acquired (VOBA) [Roll Forward]
Beginning balance			$ 2