Reinsurance (Earned Consolidated Property Casualty Insurance Premiums On Assumed And Ceded Business) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	$ 4,151	$ 3,755	$ 3,456
Assumed earned premiums	11	9	12
Ceded earned premiums	(260)	(242)	(274)
Property, Liability and Casualty Insurance Product Line [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	3,903	3,520	3,236
Assumed earned premiums	11	9	12
Ceded earned premiums	(201)	(185)	(219)
Net earned premiums	$ 3,713	$ 3,344	$ 3,029