Future Contract Benefit - Summary of Gross Premiums and Interest Accretion (UL and Other) (Details) - UL and Other - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	$ 787	$ 773	$ 1,597	$ 1,539
Interest accretion	$ 229	$ 206	$ 452	$ 410