Loss And Loss Adjustment Expense Reserves (Loss And LAE Activity) (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Abs Cdo Portfolio [Member]	Jun. 30, 2014 Second Lien Residential Mortgage Backed Securities And Reserves [Member]	Jun. 30, 2014 First Lien Residential Mortgage Backed Securities [Member]	Jun. 30, 2014 Financial Guarantee [Member]	Dec. 31, 2013 Financial Guarantee [Member]	Jun. 30, 2014 Financial Guarantee [Member] Variable Interest Entity Primary Beneficiary [Member]	Dec. 31, 2013 Financial Guarantee [Member] Variable Interest Entity Primary Beneficiary [Member]	Jun. 30, 2014 Loss And Lae Reserves [Member]	Dec. 31, 2013 Loss And Lae Reserves [Member]	Jun. 30, 2014 Recoveries On Unpaid Losses [Member]	Dec. 31, 2013 Recoveries On Unpaid Losses [Member]	Jun. 30, 2014 Insurance Loss Recoverable [Member]	Dec. 31, 2013 Insurance Loss Recoverable [Member]	Jun. 30, 2014 Insurance Loss Recoverable [Member] Classified [Member]	Dec. 31, 2013 Insurance Loss Recoverable [Member] Classified [Member]	Jun. 30, 2014 Loan Repurchase Commitments [Member] Second Lien Residential Mortgage Backed Securities And Reserves [Member] Ineligible Loan Recoveries [Member]	Dec. 31, 2013 Loan Repurchase Commitments [Member] Second Lien Residential Mortgage Backed Securities And Reserves [Member] Ineligible Loan Recoveries [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
ABS CDO exposure decrease since December 31,2007					97.00%
Aggregate ABS CDO Loss And LAE Reserves								$ 92	$ 115	$ 235	$ 226
Policyholder (Benefits) And Claims Incurred Net	12	188	62	(6)	(17)	72	27
Elimination of loss and LAE expense (benefit) as result of consolidating VIE					9	(1)	(1)
Reserves for expected future claim payments												713	847
Expected recoveries of future payments												159	206	159	206
Weighted average risk-free rate used to discount claim liability			2.01%
Total estimated insurance recoveries																				363	359
Insurance claim loss recoverable																		619	694
Insurance loss recoverable																624	694	624	694
Losses and LAE related to expected payments			$ 2			$ 19	$ 33