Abs Cdo Gross Par Outstanding

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- Definition

Asset/Liability Products Segment's deficit of cash, investments and other liquid assets at amortized costs to debt issued to third parties and affiliates at amortized costs.

+ Details

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Period Type:	instant

- Definition

Capital contribution.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Commuted gross insured exposure

+ Details

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Namespace Prefix:	mbi
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Contingency reserve release to surplus.

+ Details

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

- Definition

Gross par outstanding

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Intercompany tax payments in accordance with the Company's tax sharing agreement

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Liquid Assets

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percent loss and unearned premium reserves in qualifying assets.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Secured loan balance.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-Subparagraph b

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.23(c))

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 60

-Paragraph 60

-Subparagraph h

-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.

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 94-5

-Paragraph 8, 9

-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.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 24

-Subparagraph c

+ Details

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Businesses, Developments, Risks And Uncertainties (Details) (USD $)	9 Months Ended			9 Months Ended				3 Months Ended
	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2011 CMBS Pools, Investment Grade Corporate CDOs, A Government Supported Entity And A Municipal Gas Facility [Member]	Sep. 30, 2011 ABS CDO [Member]	Sep. 30, 2011 ABS CDO [Member] Decrease Since 2007 [Member]	Sep. 30, 2011 CRE CDO [Member]	Dec. 31, 2011 Primarily Commercial Real Estate [Member]	Sep. 30, 2011 Current Balance [Member]	May 31, 2012 Borrowing Limit [Member]	Sep. 30, 2011 CRE Loan Pools [Member]	Sep. 30, 2011 CMBS Pool [Member]
Business Acquisition [Line Items]
Statutory capital	$ 2,600,000,000		$ 2,700,000,000
Liquid assets	824,000,000		1,200,000,000
Commuted gross insured exposure				12,200,000,000				10,600,000,000
Insured par exposure							6,900,000,000				3,600,000,000	33,400,000,000
ABS CDO gross par outstanding						29,000,000,000
Gross par outstanding					6,900,000,000
Book value deficit	610,000,000
Intercompany tax payments	194,000,000
Percent loss and unearned premium reserves in qualifying assets	50.00%
Contingency reserve release to surplus	318,000,000
Secured loan balance									600,000,000	450,000,000
Capital contribution		$ 50,000,000