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Represents the cash collected against the premiums for financial guaranty insurance contracts of variable interest entity.

No definition available.

Name:	ago_FinancialGuaranteeInsuranceContractsPremiumsExpectedtobeCollected
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Period Type:	instant

[Line Items] for Financial Guarantee Insurance Premiums [Table]

No definition available.

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Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the fourth fiscal quarter following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 50
-Paragraph 3
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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Period Type:	instant

Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the eleventh through the fifteenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 50
-Paragraph 3
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the sixteenth through the twentieth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 50
-Paragraph 3
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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Namespace Prefix:	us-gaap_
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Period Type:	instant

Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the sixth through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 50
-Paragraph 3
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290

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Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Name:	us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate
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Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Namespace Prefix:	us-gaap_
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Period Type:	instant

Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of premium receivables under financial guarantee insurance contracts expected to be collected in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Namespace Prefix:	us-gaap_
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Amount of premium receivables under financial guarantee insurance contracts.

No definition available.