Investments - Schedule of Rollforward of Credit Loss Allowance for Fixed Income Securities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Ending balance	$ (17)	$ (22)
Fixed income securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Beginning balance	(36)	(13)
Credit losses on securities for which credit losses not previously reported	(3)	0
Net (increases) decreases related to credit losses previously reported	4	(9)
(Increase) decrease of allowance related to sales and other	3	0
Write-offs	15	0
Ending balance	(17)	(22)
Corporate bonds
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Ending balance	(16)	(20)
ABS
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Ending balance	$ (1)	$ (2)