Future Policy Benefit Reserves - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Insurance [Abstract]
Liability for future policy benefit, expected future gross premium, discounted, before reinsurance	$ 3,307		$ 3,307		$ 3,491
Liability for future policy benefit, weighted-average duration	11 years	11 years	11 years	11 years
Liability future policy benefit, losses recognized in current period	$ 26	$ 14	$ 49	$ 28
Liability future policy benefit, losses recognized in prior period	$ 5	$ 5	$ 13	$ 11