Income Taxes (Components Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Unearned premiums	$ 148	$ 131
Loss and loss expense reserves	106	92
Net operating loss on international earnings	28	34
Deferred international earnings	16	31
Other	55	50
Deferred tax assets before valuation allowance	353	338
Valuation allowance for international operations	31	53
Deferred tax assets net of valuation allowance	322	285
Deferred tax liabilities:
Investment gains and other, net	992	1,684
Deferred acquisition costs	171	155
Life policy reserves	112	116
Investments	31	38
Other	61	36
Total gross deferred tax liabilities	1,367	2,029
Net deferred income tax liability	$ 1,045	$ 1,744