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Loss And Loss Adjustment Expense Reserves (Schedule OF Losses And Loss Adjustment Expenses Reserves and Recoveries) (Detail) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | ---
Loss And Lae Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Loss and loss adjustment expense reserves |  | $ 541 | $ 516 |  | $ 506
Insurance Loss Recoverable [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Insurance Loss Recoverable |  | 504 | 577 |  | $ 533
U S Public Finance Insurance [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Insurance Loss Recoverable |  | 174 | 4 |  |
Loss and loss adjustment expense reserves |  | 97 | 45 |  |
International And Structured Finance Insurance [Member] | Second Lien Residential Mortgage Backed Securities And Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries | [1] | 294 | 406 |  |
Loss and loss adjustment expense reserves |  | 44 | 51 |  |
International And Structured Finance Insurance [Member] | Second Lien Residential Mortgage Backed Securities And Reserves [Member] | Excess Spread [Member] | Loss And Lae Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 14 | 24 |  |
International And Structured Finance Insurance [Member] | Second Lien Residential Mortgage Backed Securities And Reserves [Member] | Excess Spread [Member] | Insurance Loss Recoverable [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 280 | 382 |  |
International And Structured Finance Insurance [Member] | Second Lien Residential Mortgage Backed Securities And Reserves [Member] | Put-Back [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Loan repurchase commitments |  | 404 | 396 |  |
International And Structured Finance Insurance [Member] | Second Lien Residential Mortgage Backed Securities And Reserves [Member] | Variable Interest Entity Primary Beneficiary [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries | [2] | 53 | 93 |  |
Loss and loss adjustment expense reserves |  | 23 | 16 |  |
International And Structured Finance Insurance [Member] | Second Lien Residential Mortgage Backed Securities And Reserves [Member] | Variable Interest Entity Primary Beneficiary [Member] | Excess Spread [Member] | Loss And Lae Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 0 | 6 |  |
International And Structured Finance Insurance [Member] | Second Lien Residential Mortgage Backed Securities And Reserves [Member] | Variable Interest Entity Primary Beneficiary [Member] | Excess Spread [Member] | Insurance Loss Recoverable [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 53 | 87 |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Loss and loss adjustment expense reserves |  | 300 | 277 |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] | Excess Spread [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 74 | 80 |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] | Excess Spread [Member] | Loss And Lae Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 29 | 46 |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] | Excess Spread [Member] | Insurance Loss Recoverable [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 45 | 34 |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] | Variable Interest Entity Primary Beneficiary [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Loss and loss adjustment expense reserves |  | 15 | 5 |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] | Variable Interest Entity Primary Beneficiary [Member] | Excess Spread [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 18 | 8 |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] | Variable Interest Entity Primary Beneficiary [Member] | Excess Spread [Member] | Loss And Lae Reserves [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 4 |  |  |
International And Structured Finance Insurance [Member] | First Lien Rmbs [Member] | Variable Interest Entity Primary Beneficiary [Member] | Excess Spread [Member] | Insurance Loss Recoverable [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Total excess spread recoveries |  | 14 | 8 | [3],[4],[5] |
International And Structured Finance Insurance [Member] | CDOs [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Insurance Loss Recoverable |  | 0 | 148 |  |
Loss and loss adjustment expense reserves |  | 87 | 133 |  |
International And Structured Finance Insurance [Member] | CDOs [Member] | Variable Interest Entity Primary Beneficiary [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Insurance Loss Recoverable |  | 154 | 0 |  |
Loss and loss adjustment expense reserves |  | 155 | 190 |  |
International And Structured Finance Insurance [Member] | All Other [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Insurance Loss Recoverable |  | 5 | 9 |  |
Loss and loss adjustment expense reserves |  | 13 | 10 |  |
International And Structured Finance Insurance [Member] | All Other [Member] | Variable Interest Entity Primary Beneficiary [Member] |  |  |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |
Insurance Loss Recoverable |  | 0 | 0 |  |
Loss and loss adjustment expense reserves |  | $ 13 | $ 0 |  |
[1] | (1) -As of December 31, 2016 and 2015, $280 million and $382 million were included in “Insurance loss recoverable” and $14 million and $24 million were included in “Loss and loss adjustment expense reserves” on the Company’s consolidated balance sheets, respectively.
[2] | (2) -As of December 31, 2016 and 2015, $53 million and $87 million were eliminated from "Insurance loss recoverable”. As of December 31, 2015, $6 million was eliminated from “Loss and loss adjustment expense reserves” on the Company’s consolidated balance sheets, respectively.
[3] | (3) - Reflected in “Loan repurchase commitments” presented under the heading “Assets of consolidated variable interest entities” on the Company’s consolidated balance sheets.
[4] | (4) -As of December 31, 2016 and 2015, $45 million and $34 million were included in “Insurance loss recoverable” and $29 million and $46 million were included in “Loss and loss adjustment expense reserves” on the Company’s consolidated balance sheets, respectively.
[5] | (5) -As of December 31, 2016 and 2015, $14 million and $8 million were eliminated from “Insurance loss recoverable.” As of December 31, 2016, $4 million was eliminated from “Loss and loss adjustment expense reserves” on the Company’s consolidated balance sheets.

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- Definition The fair value of financial instruments that represent the right of the Trust against the seller/servicer for loans that were not compliant with the representations and warranties of the loan underwriting. The Trust has the right to demand that the transferor replace ineligible loans with a compliant loan or repurchase the non-compliant loan. + 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 The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a),(b),(c) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437 + Details
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