Income Taxes - Components of Net Deferred Tax Assets (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Unearned premium reserves, net	$ 51	$ 56
Investment basis differences	0	47
Rent	17	24
Foreign tax credit	24	24
Net operating loss	28	33
Depreciation	27	0
Deferred compensation	29	29
Other	19	4
Total deferred tax assets	195	217
Deferred tax liabilities:
Unrealized appreciation on investments	74	102
Discount on long-term debt	7	41
Market discount on investments	25	42
DAC	20	22
Investment basis differences	5	0
Loss and LAE reserve	44	44
Lease	16	17
Unrealized gains on CCS	5	11
Other	8	14
Total deferred tax liabilities	204	293
Less: Valuation allowance	24	24	$ 36
Net deferred tax assets (liabilities)	$ (33)	$ (100)