XML 45 R43.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Loss And Loss Adjustment Expense Reserves (Loss And LAE Activity) (Narrative) (Detail) (USD $) | 6 Months Ended |  | 6 Months Ended | 54 Months Ended |  | 6 Months Ended |  | 6 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2012 | Dec. 31, 2011 | Jun. 30, 2012 ABS CDO Portfolio [Member] | Jun. 30, 2012 ABS CDO Portfolio [Member] | Jun. 30, 2012 Insured Issues Designated As "Classified List" [Member] | Jun. 30, 2012 RMBS And HELOC And CES [Member] | Jun. 30, 2012 RMBS And HELOC And CES [Member] Classified [Member] Reviewed [Member] | Jun. 30, 2012 RMBS And HELOC And CES [Member] Insured Issues Designated As "Classified List" [Member] | Jun. 30, 2012 Second-Lien RMBS Reserves [Member] | Jun. 30, 2012 Ineligible Mortgage Loans [Member] | Jun. 30, 2012 Financial Guarantee [Member] | Jun. 30, 2012 Financial Guarantee [Member] Variable Interest Entity [Member] | Jun. 30, 2012 Loss And LAE Reserves [Member] | Dec. 31, 2011 Loss And LAE Reserves [Member] | Jun. 30, 2012 Recoveries On Unpaid Losses [Member] RMBS And HELOC And CES [Member] Classified [Member] Reviewed [Member] | Jun. 30, 2012 Insurance Loss Recoverable [Member] | Jun. 30, 2012 Insurance Loss Recoverable [Member] Classified [Member] | Dec. 31, 2011 Insurance Loss Recoverable [Member] Classified [Member] | Jun. 30, 2012 Loan Repurchase Commitments [Member]
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
ABS CDO exposure decrease since December 31,2007 |  |  |  | 88.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate ABS CDO Loss And LAE Reserves |  |  |  |  |  |  |  |  |  |  | $ 167,000,000 | $ 244,000,000 |  |  |  |  |  |  |
Policy holder Benefits And Claims Incurred Net | 159,000,000 |  | 2,000,000 |  |  |  |  |  | 67,000,000 |  |  |  |  |  |  |  |  |  |
Elimination Of Loss And LAE Expense As Result Of Consolidating VIE |  |  | 17,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess interest cash flows from securitizations |  |  |  |  |  | 43,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Total paid losses, net of reinsurance and collections | 325,000,000 |  |  |  |  |  |  |  | 252,000,000 |  |  |  |  |  |  |  |  |  |
Increase in insurance loss recoverable related to paid losses | 165,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reserves for expected future claim payments |  |  |  |  |  |  |  |  |  |  |  |  | 1,300,000,000 | 1,400,000,000 |  |  |  |  |
Expected recoveries of future payments | 508,000,000 | 562,000,000 |  |  |  |  |  |  |  |  |  |  | 508,000,000 | 562,000,000 |  |  |  |  |
Number of insured issues reviewed |  |  |  |  | 34 |  | 29 | 34 |  |  |  |  |  |  |  |  |  |  |
Number of insured issues reviewed with recorded recoveries |  |  |  |  |  |  | 29 |  |  |  |  |  |  |  | 26 |  |  |  |
Number of transactions received consideration and excluded from loan files reviewed with potential recoveries | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average risk-free rate used to discount claim liability | 1.30% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total estimated recoveries from ineligible loans |  |  |  |  |  |  |  |  | $ 3,200,000,000 | $ 3,200,000,000 |  |  |  |  |  | $ 2,200,000,000 | $ 3,185,000,000 | $ 3,032,000,000 | $ 1,000,000,000

X
- Definition ABS CDO exposure decrease. + References No definition available. + Details
Name: | mbi_AbsCdoExposureDecrease
Namespace Prefix: | mbi_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate ABS CDO loss and LAE reserves. + References No definition available. + Details
Name: | mbi_AggregateAbsCdoLossAndLaeReserves
Namespace Prefix: | mbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Elimination Of Loss And LAE Expense As Result Of Consolidating VIEs + References No definition available. + Details
Name: | mbi_EliminationOfLossAndLaeExpenseAsResultOfConsolidatingVie
Namespace Prefix: | mbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Excess Interest Cash Flows From Securitizations + References No definition available. + Details
Name: | mbi_ExcessInterestCashFlowsFromSecuritizations
Namespace Prefix: | mbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Gross reserve, recoveries on unpaid losses + References No definition available. + Details
Name: | mbi_GrossReserveRecoveriesOnUnpaidLosses
Namespace Prefix: | mbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Increase decrease in carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts related to recoveries related to commitments to recoveries on paid claims. + References No definition available. + Details
Name: | mbi_IncreaseDecreaseInInsuranceLossRecoverableRelatedToPaidLosses
Namespace Prefix: | mbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | mbi_LossAndLossAdjustmentExpenseReservesLineItems
Namespace Prefix: | mbi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Insured Issues Reviewed + References No definition available. + Details
Name: | mbi_NumberOfInsuredIssuesReviewed
Namespace Prefix: | mbi_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Insured Issues Reviewed With Recorded Recoveries + References No definition available. + Details
Name: | mbi_NumberOfInsuredIssuesReviewedWithRecordedRecoveries
Namespace Prefix: | mbi_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Transactions Received Consideration And Excluded From Loan Files Reviewed With Potential Recoveries + References No definition available. + Details
Name: | mbi_NumberOfTransactionsReceivedConsiderationAndExcludedFromLoanFilesReviewedWithPotentialRecoveries
Namespace Prefix: | mbi_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Reserves For Expected Future Claim Payments + References No definition available. + Details
Name: | mbi_ReservesForExpectedFutureClaimPayments
Namespace Prefix: | mbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Supplementary Insurance Information Paid Losses Net Of Reinsurance And Collections + References No definition available. + Details
Name: | mbi_SupplementaryInsuranceInformationPaidLossesNetOfReinsuranceAndCollections
Namespace Prefix: | mbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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
Name: | us-gaap_EstimatedInsuranceRecoveries
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 163 -Paragraph 30 -Subparagraph f(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsClaimLiabilityWeightedAverageRiskFreeDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Provision for benefits, claims and claims settlement expenses incurred during the period net of the effects of contracts assumed and ceded. + 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 SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 5 -Article 7 + Details
Name: | us-gaap_PolicyholderBenefitsAndClaimsIncurredNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration