Reserves for Future Policy Benefits (Details) - Annuitization Benefit - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning Balance	$ 642	$ 713
Incurred	63	10
Paid	77	25
Change in unrealized investment gains and losses	17	(42)
Ending Balance	645	656
Movement in Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable [Roll Forward]
Beginning Balance	27	26
Incurred	2	10
Paid	0	1
Ending Balance	$ 29	$ 35