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Loss And Loss Adjustment Expense Reserves (Schedule Of Total Estimated Recoveries From Ineligible Second-Lien Mortgage Loans) (Detail) (Ineligible Mortgage Loans [Member], USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011
Ineligible Mortgage Loans [Member] |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |
Total Estimated Recoveries from Ineligible Mortgage Loans, Beginning Balance | $ 3,119 | $ 2,517
Accretion of Future Collections | 36 | 65
Changes in Discount Rates | 2 | 35
Recoveries (Collections) |  | (86)
Changes in Amount of Collections |  | 29
Changes in Assumptions | 426 | 559
Total Estimated Recoveries from Ineligible Mortgage Loans, Ending Balance | $ 3,583 | $ 3,119

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- Definition Estimated Insurance Recoveries Accretion Of Future Collections + References No definition available. + Details
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- Definition Estimated Insurance Recoveries Change In Assumptions + References No definition available. + Details
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- Definition Estimated Insurance Recoveries Change In Discount Rate + References No definition available. + Details
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- Definition Estimated Insurance Recoveries Collections + References No definition available. + Details
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- 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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