Reinsurance - Schedule of Effect of Reinsurance on Premiums Earned and Benefits Incurred and Reserve Changes (Details) - Life Insurance Product Line - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Net Premiums Earned
Direct	$ 193	$ 565	$ 799	$ 1,370
Ceded	(19)	(21)	(58)	(64)
Net	174	544	741	1,306
Net Product Fees
Direct	188	178	547	537
Ceded	(32)	(11)	(85)	(35)
Net	156	167	462	502
Net Benefits Incurred
Direct	56	1,237	1,815	2,871
Ceded	(30)	(56)	(156)	(173)
Net	$ 26	$ 1,181	$ 1,659	$ 2,698

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