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The reference rate for the variable rate for income distributions on the financial 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.

No definition available.

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Represents the number of custodial trusts with whom the entity entered into put agreements.

No definition available.

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Represents the amount of cumulative strip par exposure that has been terminated on a consensual basis.

No definition available.

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Investing Activities, Intercompany Debt

No definition available.

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Represents the maximum debt-to-capital ratio which the entity is required to maintain per the terms of the credit agreement.

No definition available.

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Represents the amount to be added to the calculation for the minimum consolidated net worth required to be maintained per the terms of the credit agreement, in the event that the borrowing capacity has already been reduced.

No definition available.

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Represents the percentage of aggregate consolidated net income for a specified period to be added to the calculation for the minimum consolidated net worth required to be maintained per the terms of the credit agreement.

No definition available.

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Represents the minimum net worth required to be maintained per the terms of the credit agreement, as a percentage of the consolidated net worth on a specified date.

No definition available.

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Line of Credit Facility, Interest Rate at Period End as Percentage of Federal Rate

No definition available.

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Related Party Transaction, Maximum Borrowing Capacity

No definition available.

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Period in a rate setting interval for auction market preferred securities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

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

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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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.

Reference 1: 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

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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 210.5-02.19(b),22(b))

-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 19, 22

-Article 5

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Amount that would be paid, determined under the conditions specified in the contract, if the holder of the share has the right to redeem the shares.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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The maximum amount that the issuer could be required to pay to redeem the instrument by physical settlement, if applicable.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6940734&loc=d3e22047-110879

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Name:	us-gaap_BusinessAcquisitionAxis=ago_RadianAssetAssuranceIncMember
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Name:	us-gaap_DebtInstrumentAxis=ago_Quibs6875PercentMember
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Name:	us-gaap_DebtInstrumentAxis=ago_SeniorNotes5.0PercentMember
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Name:	us-gaap_DebtInstrumentAxis=ago_SeniorNotes70PercentMember
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Name:	us-gaap_LineOfCreditFacilityAxis=ago_DexiaCreditLocalNYMember
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