Contracts Accounted for as Insurance - Effect of Reinsurance on Premiums Written, Premiums Earned and Loss and LAE (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Premiums Written:
Direct	$ 436	$ 307	$ 377
Assumed	4	50	(17)
Ceded	(6)	(16)	0
Net	434	341	360
Premiums Earned:
Direct	378	319	469
Assumed	32	28	28
Ceded	(7)	(3)	(3)
Net earned premiums	403	344	494
Loss and LAE (benefit):
Direct	(30)	157	32
Assumed	3	8	(17)
Ceded	1	(3)	1
Loss and LAE (benefit)	$ (26)	$ 162	$ 16

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Policyholder Benefits and Claims Incurred, Assumed, (Benefit) Loss

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Policyholder Benefits and Claims Incurred, Ceded, Benefit (Loss)

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Amount of earned premiums assumed from other entities.

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Amount of written premiums assumed from other entities.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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