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The maximum percentage of statutory capital that may be paid out as dividends without prior approval from a regulatory agency.

No definition available.

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The maximum percentage of statutory capital and surplus that may be paid out as dividends without prior approval from a regulatory agency.

No definition available.

Name:	ago_DividendPaymentRestrictionsSchedulePercentageOfStatutoryCapitalAndSurplus
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Dividend Payments Restrictions Schedule, Statutory Surplus

No definition available.

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Holding Company's Percent Ownership of Common Stock

No definition available.

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Represents the discount rate used to calculate present value for surveillance purposes.

No definition available.

Name:	ago_InsuredFinancialObligationsDiscountRate
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Statutory Accounting Practices, Contingency Reserves Reassumed

No definition available.

Name:	ago_StatutoryAccountingPracticesContingencyReservesReassumed
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Statutory Accounting Practices, Contingency Reserves Reassumed, Amount

No definition available.

Name:	ago_StatutoryAccountingPracticesContingencyReservesReassumedAmount
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Statutory Accounting Practices, Contingency Reserves Reassumed, Release of Assets

No definition available.

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Statutory Accounting Practices, Contingency Reserves Reassumed, Year Three, Percentage

No definition available.

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Statutory Accounting Practices, Contingency Reserves Reassumed, Year Two, Percentage

No definition available.

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Statutory Accounting Practices, Contingency Reserves, Release of Assets

No definition available.

Name:	ago_StatutoryAccountingPracticesContingencyReservesReleaseofAssets
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Statutory Accounting Practices, Intercompany Transaction, Ceded Premiums

No definition available.

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Statutory Accounting Practices, Intercompany Transaction, Ceded Unearned Premiums

No definition available.

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Statutory Accounting Practices, Intercompany Transaction, Payments for Interest in Subsidiaries

No definition available.

Name:	ago_StatutoryAccountingPracticesIntercompanyTransactionPaymentsforInterestinSubsidiaries
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Statutory Accounting Practices, Reassumed Contingency Reserves

No definition available.

Name:	ago_StatutoryAccountingPracticesReassumedContingencyReserves
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Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval, Available in Next Fiscal Quarter

No definition available.

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Statutory Accounting Practices, Statutory Threshold for Dividend Payments, Percentage of Adjusted Net Investment Income

No definition available.

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Statutory Accounting Practices, Statutory Threshold for Dividend Payments, Percentage of Policyholder' Surplus

No definition available.

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Unencumbered Assets which are not held in trust for the benefit of cedants.

No definition available.

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Amount of statutory capital and surplus computed using prescribed or permitted statutory accounting practice.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 505

-Section 50

-Paragraph 1

-Subparagraph (b)

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

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(e))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph e

-Article 4

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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.

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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 24

-Subparagraph c

-Article 7

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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.

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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Name:	dei_LegalEntityAxis=ago_AssuredGuarantyReMember
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Name:	dei_LegalEntityAxis=ago_MunicipalAssuranceCorpHoldingsMember
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