Income Taxes (Components Of Deferred Tax Assets and Liabilities) (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred tax liabilities:
Unearned premium reserve	$ 40	$ 48
Deferred acquisition costs	5	10
Net unrealized gains and losses in accumulated other comprehensive income	21	25
Net deferred taxes on VIEs	34	53
Other	0	6
Total gross deferred tax liabilities	100	142
Deferred tax assets:
Compensation and employee benefits	8	9
Accrued interest	233	210
Partnership basis difference	0	10
Loss and loss adjustment expense reserves	45	98
Net operating loss	777	656
Foreign tax credits	58	61
Other-than-temporary impairments and capital loss carryforward	9	0
Net unrealized losses on insured derivatives	0	10
Net gains and losses on financial instruments at fair value and foreign exchange	28	54
Other	4	0
Total gross deferred tax assets	1,162	1,108
Valuation allowance	1,062	$ 966
Net deferred tax asset	$ 0