Future Contract Benefit - Summary of Gross Premiums and Interest Accretion (UL and Other) (Details) - UL and Other - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Gross assessments	$ 2,937	$ 3,219	$ 2,818
Interest accretion	$ 863	$ 775	$ 626