Schedule V - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance as of January 1	$ 0	$ 2	$ 3
Allowance for losses on commercial mortgage loans	76	(1)	(1)
Balance as of December 31	26	0	2
Reinsurance Recoverable, Credit Loss Expense (Reversal)	1	0	0
Reinsurance Recoverable, Allowance for Credit Loss, Period Increase (Decrease)	0	0	0
Less: Allowance for credit losses on reinsurance recoverable	18	0	0	$ 0
Writeoffs	0
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Less: Allowance for credit losses on reinsurance recoverable		17
Private placement
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance as of January 1	1	2
Balance as of December 31	89	1	2
Writeoffs	(3)	0	0
Private placement | Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance as of January 1	16
Balance as of December 31		16
Valuation allowance on deferred tax assets
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	379	638	653
Charged to Costs and Expenses	(26)	(259)	(15)
Write-offs/Payments/Other	0	0	0
Ending Balance	$ 353	$ 379	$ 638