XML 99 R93.htm IDEA: XBRL DOCUMENT v2.4.1.9

Debt (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Jan. 16, 2008
Debt Instrument [Line Items]
Aggregate principal amount in excess of stated amount	10mbi_AggregatePrincipalAmountInExcessOfFailuretoMakePaymentAtMaturity
Surplus notes outstanding	940us-gaap_SurplusNotes	[1]	940us-gaap_SurplusNotes	[1]	1,000us-gaap_SurplusNotes
Surplus notes purchased at par value	13mbi_SurplusNotesAtParValueOwnedByCorporateSegment
Senior notes at par value owned by National	136mbi_SeniorNotesAtParValueOwnedByNational
Surplus notes repurchased at outstanding par value	47mbi_SurplusNotesRepurchasedAtOutstandingParValue
Surplus notes, weighted average price per unit	77.08mbi_SurplusNotesWeightedAveragePricePerUnit
Long-term debt	592us-gaap_DebtInstrumentCarryingAmount		592us-gaap_DebtInstrumentCarryingAmount
MBIA Inc Senior Notes [Member]
Debt Instrument [Line Items]
Accrued interest	8us-gaap_InterestPayableCurrentAndNoncurrent / us-gaap_DebtInstrumentAxis = mbi_MbiaIncSeniorNotesMember		8us-gaap_InterestPayableCurrentAndNoncurrent / us-gaap_DebtInstrumentAxis = mbi_MbiaIncSeniorNotesMember
MBIA Corp Surplus Notes [Member]
Debt Instrument [Line Items]
Long-term debt, interest rate	14.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = mbi_MbiaCorpSurplusNotesMember
Interest rate terms	interest rate of 14% until January 15, 2013 and thereafter have an interest rate of three-month LIBOR plus 11.26%
Debt instrument, base reference rate	three-month LIBOR
Debt instrument, basis spread on variable rate	11.26%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = mbi_MbiaCorpSurplusNotesMember
Medium Term Notes [Member]
Debt Instrument [Line Items]
Annual interest rates, minimum	0.00%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember		0.00%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember
Annual interest rates, maximum	9.08%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember		8.93%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember
Weighted average interest rate	2.44%us-gaap_DebtWeightedAverageInterestRate / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember		2.67%us-gaap_DebtWeightedAverageInterestRate / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember
Medium Term Notes [Member] | Conduits [Member]
Debt Instrument [Line Items]
Par value redeemed	129us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember / us-gaap_ProductOrServiceAxis = mbi_ConduitsMember
Weighted average percent of par	97.00%mbi_DebtInstrumentRepurchasedPercentOfParValue / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember / us-gaap_ProductOrServiceAxis = mbi_ConduitsMember
Medium Term Notes [Member] | Global Funding Limited [Member]
Debt Instrument [Line Items]
Par value redeemed	122us-gaap_DebtInstrumentRepurchasedFaceAmount / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember / us-gaap_ProductOrServiceAxis = mbi_GlobalFundingLimitedMember
Weighted average percent of par	98.00%mbi_DebtInstrumentRepurchasedPercentOfParValue / us-gaap_CreditFacilityAxis = us-gaap_MediumTermNotesMember / us-gaap_ProductOrServiceAxis = mbi_GlobalFundingLimitedMember
Investment Agreement Obligations [Member]
Debt Instrument [Line Items]
Annual interest rates, minimum	3.48%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum / us-gaap_CreditFacilityAxis = mbi_InvestmentAgreementObligationsMember		0.21%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum / us-gaap_CreditFacilityAxis = mbi_InvestmentAgreementObligationsMember
Annual interest rates, maximum	7.38%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum / us-gaap_CreditFacilityAxis = mbi_InvestmentAgreementObligationsMember		7.38%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum / us-gaap_CreditFacilityAxis = mbi_InvestmentAgreementObligationsMember
Weighted average interest rate	5.50%us-gaap_DebtWeightedAverageInterestRate / us-gaap_CreditFacilityAxis = mbi_InvestmentAgreementObligationsMember		5.10%us-gaap_DebtWeightedAverageInterestRate / us-gaap_CreditFacilityAxis = mbi_InvestmentAgreementObligationsMember
[1] Callable on or after January 15, 2018 and every fifth anniversary thereafter at 100.00.

X

- Definition

Aggregate Principal Amount In Excess Of FailureTo Make Payment At Maturity

+ References

No definition available.

+ Details

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Namespace Prefix:	mbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Debt instruments repurchased weighted average percent of par value.

+ References

No definition available.

+ Details

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Namespace Prefix:	mbi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Par value of MBIA Inc. senior notes owned by National as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	mbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Surplus Notes At Par Value Owned By Corporate Segment

+ References

No definition available.

+ Details

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Namespace Prefix:	mbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Surplus Notes Repurchased At Outstanding Par Value

+ References

No definition available.

+ Details

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Namespace Prefix:	mbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Surplus Notes Weighted Average Price Per Unit

+ References

No definition available.

+ Details

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Namespace Prefix:	mbi_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentDescriptionOfVariableRateBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Maximum contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

X

- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:stringItemType
Balance Type:	na
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X

- Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.15(a))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph a

-Article 7



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

X

- Definition

Financial instruments issued by insurance entities (surplus notes) that are includable in surplus for statutory accounting purposes as prescribed or permitted by state laws and regulations that are liabilities of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6486086&loc=d3e24387-158525

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_MediumTermNotesMember
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Period Type:

X

- Details

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Period Type:

X

- Details

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