Reserves for Future Policy Benefits (Details) - Annuaitization Benefit - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning liability balance	$ 638	$ 635
Incurred	37	18
Paid	26	22
Change in unrealized investment gains and losses	(8)	(2)
Ending liability balance	641	629
Movement in Liabilities for Guarantees on Long-Duration Contracts, Reinsurance Recoverable [Roll Forward]
Beginning reinsurance recoverable asset	28	31
Incurred	18	(1)
Paid	0	0
Ending reinsurance recoverable asset	$ 46	$ 30