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Represents the premiums received and receivable, ceding commissions, and the losses paid and payable. This element refers to the gain (loss) included in earnings.

No definition available.

Name:	ago_CreditDerivativeRealizedGainLossandOtherSettlements
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Represents the net realized gain included in earning related to credit derivatives.

No definition available.

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Represents the principal amounts of the underlying insured obligations accounted for as credit derivatives, net of protection purchased, that were terminated during the period.

No definition available.

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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.

No definition available.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

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

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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