Loss And Loss Adjustment Expense Reserves (Schedule Of Present Value Of The Probability-Weighted Future Claim Payments And Recoveries) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Loss And Loss Adjustment Expense Reserves [Line Items]
LAE insurance loss recoverable	$ 0	$ 0
Insurance loss recoverable	(527)	(533)
Reinsurance recoverable on unpaid losses	6	6
Reinsurance recoverable on unpaid LAE	1	1
Reinsurance recoverable on paid and unpaid losses	7	7
Loss Reserves Claim Liability [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	464	464
Lae Reserves [Member] | Classified [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	35	42
Loss And Lae Reserves [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Loss and loss adjustment expense reserves	$ 499	$ 506