Reserves for Future Policy Benefits (Details) - Annuitization Benefit - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning Balance	$ 635	$ 642
Incurred	18	27
Paid	22	28
Change in unrealized investment gains and losses	(2)	7
Ending Balance	629	648
Movement in Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable [Roll Forward]
Beginning Balance	31	27
Incurred	(1)	5
Paid	0	2
Ending Balance	$ 30	$ 30