Loss And Loss Adjustment Expense Reserves (Schedule Of Present Value Of The Probability-Weighted Future Claim Payments And Recoveries) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Loss Reserves Claim Liability [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	$ 449,000,000	$ 580,000,000
Lae Reserves [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	68,000,000	61,000,000
Loss And Lae Reserves [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	517,000,000	641,000,000
Loss And Lae Reserves [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	517,000,000	641,000,000
Insurance Loss Recoverable [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance loss recoverable	(575,000,000)	(694,000,000)
Insurance Loss Recoverable [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Insurance claim loss recoverable	(568,000,000)	(694,000,000)
LAE insurance loss recoverable	(7,000,000)	0
Insurance loss recoverable	(575,000,000)	(694,000,000)
Reinsurance recoverable on unpaid losses	6,000,000	7,000,000
Reinsurance recoverable on unpaid LAE	1,000,000	1,000,000
Reinsurance recoverable on paid losses	0	0
Reinsurance recoverable on paid and unpaid losses	$ 7,000,000	$ 8,000,000