Income Taxes - Significant components of deferred tax assets and liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Federal net operating loss carryforwards	$ 12	$ 15
Foreign underwriting losses	9	6
Capital loss carryforwards	0	7
Insurance claims and reserves	249	240
Employee benefits	112	102
Other, net	26	45
Total deferred tax assets before valuation allowance	408	415
Valuation allowance against deferred tax assets	(25)	(29)
Total deferred tax assets	383	386
Deferred tax liabilities:
Investment securities	(200)	(129)
Deferred policy acquisition costs	(61)	(55)
Insurance claims and reserves transition liability	(17)	(21)
Real estate, property and equipment	(29)	(33)
Total deferred tax liabilities	(307)	(238)
Net deferred tax asset	$ 76	$ 148