Insurance Contracts - Effect of Reinsurance on Premiums Written and Earned (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]
Direct Premiums Written	$ 30	$ (2)
Assumed Reinsurance Premiums Written	0	0
Ceded Reinsurance Premiums Written	18	7
Premiums written, net of reinsurance	(12)	9
Direct Premiums Earned	23	17
Assumed Reinsurance Premiums Earned	0	0
Ceded Reinsurance Premiums Earned	$ 8	$ 3

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Amount of earned premiums assumed from other entities.

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