Income Taxes (Components Of Deferred Tax Assets And Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Loss and loss expense reserves	$ 206	$ 202
Unearned premiums	137	124
Investments	19	31
Other	46	39
Total	408	396
Deferred tax liabilities:
Unrealized investment gains and other	807	605
Deferred acquisition costs	178	163
Life policy reserves	86	65
Other	10	16
Total	1,081	849
Net deferred tax liability	$ 673	$ 453