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Loss And Loss Adjustment Expense Reserves (Loss And LAE Activity) (Narrative) (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Policyholder (Benefits) And Claims Incurred Net | $ 123 | $ 133 | $ 117
Weighted average risk-free rate used to discount claim liability | 1.82% | 1.72% |
Insurance loss recoverable | $ 577 | $ 533 | 694
CDO Portfolio [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Policyholder (Benefits) And Claims Incurred Net | 29 |  |
CDO Portfolio [Member] | Variable Interest Entity Primary Beneficiary [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Elimination Of Loss And LAE Expense (Benefit) As Result Of Consolidating VIEs | (35) |  |
Second Lien Residential Mortgage Backed Securities And Reserves [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Policyholder (Benefits) And Claims Incurred Net | 63 | 70 | (2)
First Lien Residential Mortgage Backed Securities [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Policyholder (Benefits) And Claims Incurred Net | 34 | 65 | (70)
Financial Guarantee [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Aggregate CDO Loss And LAE Reserves | 133 | 111 |
Financial Guarantee [Member] | CDO Portfolio [Member] | Variable Interest Entity Primary Beneficiary [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Elimination Of Loss And Lae Reserves As Result Of Consolidating VIEs | 190 | 225 |
Loss And Lae Reserves [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Reserves for expected future claim payments | 616 | 653 |
Expected recoveries of future payments | 100 | 147 | 206
Recoveries On Unpaid Losses [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Expected recoveries of future payments | 100 | 147 | 206
Insurance Loss Recoverable [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Insurance loss recoverable | 577 | 533 | 694
Insurance Loss Recoverable [Member] | Classified [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Insurance claim loss recoverable | 571 | 533 |
Insurance loss recoverable | 577 | 533 |
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] |  |  |
Total estimated insurance recoveries | 396 | 379 |
Remedial Actions For Insured Obligations [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Policyholder (Benefits) And Claims Incurred Net | $ 26 | $ 36 | $ 57

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- Definition Carrying amount as of the balance sheet date of paid insurance policy claims and LAE expense expected to be recovered. + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 + Details
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- Definition This element represents the weighted average risk free rate used to discount the claim liability related to financial guarantee insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
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- Definition Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.5) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6811-158387 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 5 -Article 7 + Details
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