Income Taxes (Components Of Deferred Tax Assets and Liabilities) (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Deferred tax liabilities:
Unearned premium revenue	$ 36	$ 40
Deferred acquisition costs	4	5
Net gains on financial instruments at fair value and foreign exchange	121	0
Net unrealized gains and losses in accumulated other comprehensive income	0	21
Net deferred taxes on VIEs	27	34
Total gross deferred tax liabilities	188	100
Deferred tax assets:
Compensation and employee benefits	8	8
Accrued interest	259	233
Loss and loss adjustment expense reserves	148	45
Net operating loss	814	777
Foreign tax credits	57	58
Other-than-temporary impairments and capital loss carryforward	16	9
Net gains and losses on financial instruments at fair value and foreign exchange	0	28
Net unrealized gains and losses in accumulated other comprehensive income	72	0
Other	13	4
Total gross deferred tax assets	1,387	1,162
Valuation allowance	1,199	1,062
Net deferred tax asset	$ 0	$ 0