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Loss And Loss Adjustment Expense Reserves (Loss And LAE Activity) (Narrative) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015 | Dec. 31, 2015
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Policyholder (Benefits) And Claims Incurred Net | $ 77 | $ 46 | $ 99 | $ 40 |
Weighted average risk-free rate used to discount claim liability |  |  | 1.18% |  |
Insurance claim loss recoverable | 363 |  | $ 363 |  | $ 571
Insurance loss recoverable | 365 |  | 365 |  | 577
CDO Portfolio [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Policyholder (Benefits) And Claims Incurred Net | 9 |  | (22) |  |
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 | 8 |  | 20 |  |
Second Lien Residential Mortgage Backed Securities And Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Policyholder (Benefits) And Claims Incurred Net | 21 | 36 | 34 | 29 |
First Lien Residential Mortgage Backed Securities [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Policyholder (Benefits) And Claims Incurred Net | 35 | (26) | 61 | (16) |
Financial Guarantee [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Aggregate CDO Loss And LAE Reserves | 104 |  | 104 |  | 133
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 | 206 |  | 206 |  | 190
Loss And Lae Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Reserves for expected future claim payments | 637 |  | 637 |  | 616
Expected recoveries of future payments | 91 |  | 91 |  | 100
Recoveries On Unpaid Losses [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Expected recoveries of future payments | 91 |  | 91 |  | 100
Insurance Loss Recoverable [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Insurance loss recoverable | 365 |  | 365 |  | 577
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 | 401 |  | 401 |  | $ 396
Remedial Actions For Insured Obligations [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Policyholder (Benefits) And Claims Incurred Net | $ 20 | $ 7 | $ 28 | $ 5 |

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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 + 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 + Details
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