Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Reserves And Recoverables For Insured Obligations) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010	Dec. 31, 2009
Loss And Loss Adjustment Expense Reserves [Line Items]
Reinsurance recoverable	$ 16	[1]
Loss Reserves (Claim Liability) [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss adjustment expense reserves	781		1,059
LAE Reserves [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss adjustment expense reserves	55		70
Reinsurance recoverable on unpaid losses	0		1
Loss And LAE Reserves [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss adjustment expense reserves	836		1,129	1,580
Loss And LAE Reserves [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss adjustment expense reserves	836		1,129
Insurance Loss Recoverable [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
LAE insurance loss recoverable	(14)
Insurance claim loss recoverable	(3,032)		(2,531)
LAE reserves	(3,046)		(2,531)
Reinsurance recoverable on unpaid losses	15		14
Reinsurance recoverable on paid losses	1		0
Reinsurance recoverable on paid and unpaid losses	$ 16		$ 15

[1] reinsurance recoverable of $16 million comprised recoverables on paid and unpaid losses of $1 million and $15 million, respectively.