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, 2023	Dec. 31, 2022	Dec. 31, 2021
Premiums Written:
Direct	$ 307	$ 377	$ 355
Assumed	50	(17)	22
Ceded	(16)	0	0
Net	341	360	377
Premiums Earned:
Direct	319	469	385
Assumed	28	28	32
Ceded	(3)	(3)	(3)
Net earned premiums	344	494	414
Loss and LAE (benefit):
Direct	157	32	(203)
Assumed	8	(17)	5
Ceded	(3)	1	(22)
Loss and LAE (benefit)	$ 162	$ 16	$ (220)

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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 written premiums assumed from other entities.

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