XML 77 R63.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Loss And Loss Adjustment Expense Reserves (Schedule Of Financial Guarantees And Related Claim Liability) (Detail) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) issue policy | Dec. 31, 2016 USD ($) issue policy
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Number of policies | policy |  | 375 | 430
Number of issues | issue | [1] | 144 | 149
Remaining weighted average contract period (in years) |  | 8 years 10 months 24 days | 7 years 1 month 6 days
Principal | [2] | $ 8,964 | $ 10,285
Interest | [2] | 8,481 | 5,683
Total | [2] | 17,445 | 15,968
Gross claim liability | [3] | 1,082 | 718
Less: Gross potential recoveries | [4] | 782 | 770
Discount, net | [5] | (178) | (75)
Net claim liability (recoverable) |  | 478 | 23
Unearned premium revenue |  | $ 90 | $ 85
Caution List Low [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Number of policies | policy |  | 89 | 90
Number of issues | issue | [1] | 20 | 17
Remaining weighted average contract period (in years) |  | 7 years 4 months 24 days | 7 years 6 months
Principal | [2] | $ 2,764 | $ 2,917
Interest | [2] | 2,676 | 2,795
Total | [2] | 5,440 | 5,712
Gross claim liability | [3] | 0 | 0
Less: Gross potential recoveries |  | 0 | 0
Discount, net | [5] | 0 | 0
Net claim liability (recoverable) |  | 0 | 0
Unearned premium revenue |  | $ 9 | $ 9
Caution List Medium [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Number of policies | policy |  | 5 | 6
Number of issues | issue | [1] | 4 | 4
Remaining weighted average contract period (in years) |  | 4 years 3 months 18 days | 3 years 4 months 24 days
Principal | [2] | $ 13 | $ 17
Interest | [2] | 3 | 4
Total | [2] | 16 | 21
Gross claim liability | [3] | 0 | 0
Less: Gross potential recoveries |  | 0 | 0
Discount, net | [5] | 0 | 0
Net claim liability (recoverable) |  | 0 | 0
Unearned premium revenue |  | $ 0 | $ 0
Caution List High [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Number of policies | policy |  | 1 | 3
Number of issues | issue | [1] | 1 | 2
Remaining weighted average contract period (in years) |  | 8 years 8 months 12 days | 7 years 2 months 12 days
Principal | [2] | $ 104 | $ 320
Interest | [2] | 46 | 107
Total | [2] | 150 | 427
Gross claim liability | [3] | 0 | 0
Less: Gross potential recoveries |  | 0 | 0
Discount, net | [5] | 0 | 0
Net claim liability (recoverable) |  | 0 | 0
Unearned premium revenue |  | $ 4 | $ 8
Classified List [Member] |  |  |
Loss And Loss Adjustment Expense Reserves [Line Items] |  |  |
Number of policies | policy |  | 280 | 331
Number of issues | issue | [1] | 119 | 126
Remaining weighted average contract period (in years) |  | 9 years 8 months 12 days | 7 years
Principal | [2] | $ 6,083 | $ 7,031
Interest | [2] | 5,756 | 2,777
Total | [2] | 11,839 | 9,808
Gross claim liability | [3] | 1,082 | 718
Less: Gross potential recoveries | [4] | 782 | 770
Discount, net | [5] | (178) | (75)
Net claim liability (recoverable) |  | 478 | 23
Unearned premium revenue |  | $ 77 | $ 68
[1] | An “issue” represents the aggregate of financial guarantee policies that share the same revenue source for purposes of making debt service payments on the insured debt.
[2] | Represents contractual principal and interest payments due by the issuer of the obligations insured by MBIA.
[3] | The gross claim liability with respect to Puerto Rico and Zohar II exposures are net of expected recoveries for policies in a net payable position.
[4] | Gross potential recoveries with respect to certain Puerto Rico exposures are net of the claim liability for policies in a net recoverable position.
[5] | Represents discount related to Gross Claim Liability and Gross Potential Recoveries.

X
- Definition Loss And Loss Adjustment Expense Reserves [Line Items] + References No definition available. + Details
Name: | mbi_LossAndLossAdjustmentExpenseLineItems
Namespace Prefix: | mbi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Remaining weighted average contract period of financial guarantee insurance contracts, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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)(5)(ii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
Name: | us-gaap_InsuredFinancialObligationsWithCreditDeteriorationRemainingWeightedAverageContractPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition This element represents the gross claim liability for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(iv) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossClaimLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This element represents the amount of insured contractual payments outstanding on the underlying insured obligations for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(iii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This element represents the amount of insured contractual payments outstanding attributable to interest accrued on the underlying insured obligations for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(iii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This element represents the amount of insured contractual payments outstanding attributable to the principal of the underlying insured obligations for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + 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)(5)(iii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingPrincipal
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This element represents the net claim liability related to financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(vii) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNetClaimLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This element represents the number of issued and outstanding contracts for each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + 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)(5)(i) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNumberOfContractsIssuedAndOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition This element represents the gross potential recoveries against the gross claim liability for financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(v) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityGrossPotentialRecoveries
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This element represents the net discount consisting of the difference between the discount related to the claim liability for and potential recoveries thereof related to financial guarantee insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + 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)(5)(vi) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityNetDiscount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This element represents the amount of unearned premium revenue, reported on or included in the statement of financial position, related to financial guarantee insurance contracts and presented in the schedule of insured financial obligations with credit deterioration in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=34726416&loc=SL5751133-161288 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(ix) -URI http://asc.fasb.org/extlink&oid=6933314&loc=SL5749324-161292 + Details
Name: | us-gaap_ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionUnearnedPremiumRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | mbi_SurveillanceCategoriesAxis=mbi_CautionListLowMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | mbi_SurveillanceCategoriesAxis=mbi_CautionListMediumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | mbi_SurveillanceCategoriesAxis=mbi_CautionListHighMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | mbi_SurveillanceCategoriesAxis=mbi_ClassifiedListMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |