Summary of Significant Accounting Policies - Pre-Transition LFPB to Adjusted Opening Balance (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2021	Dec. 31, 2020
Present value of future net premiums
Balance	$ 13,480	$ 13,959	$ 18,010	$ 19,132
Effect of changes in cash flow assumptions	$ 36		$ 538	176
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2018-12 [Member]
Previously Reported
Present value of future net premiums
Balance	$ 10,151			13,318
Reclassification of reserves for policyholders currently receiving benefits to Future policy benefits
Present value of future net premiums
Effect of changes in cash flow assumptions				2,844
De-recognition of shadow reserves
Present value of future net premiums
Effect of changes in cash flow assumptions				(3,293)
Re-measurement using an upper-medium grade fixed income instrument yield discount rate
Present value of future net premiums
Effect of changes in cash flow assumptions				6,255
Other adjustments
Present value of future net premiums
Effect of changes in cash flow assumptions				$ 8