Future Policy Benefits Reserves - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Insurance [Abstract]
Liability for future policy benefit, gross premium income	$ 115	$ 120
Liability for future policy benefit, expected future gross premium, discounted, before reinsurance	$ 4,000	$ 4,600
Liability for future policy benefit, weighted-average duration	12 years	12 years
Liability for future policy benefit, adverse development, expense	$ 13	$ 0
Liability future policy benefit, losses recognized in prior period	$ 11	$ 1