Represents the amount of payment on the termination of credit derivatives transactions which the defendant owes to plaintiff as per the calculation of plaintiff.

No definition available.

+ Details

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Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Gain Contingency, Allegations, Payment For Termination of Other Credit Derivative Transactions Owed by Plaintiff to Defendant As Per Calculation of Defendant

+ References

No definition available.

+ Details

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Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4K
-Subparagraph (f)
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4K

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
-Section 50
-Paragraph 4K
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4K

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4L
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4L

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4K
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4K

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain from litigation settlement for amount awarded from other party. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483049/450-30-50-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ago_AssuredGuarantyFinancialProductsIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ago_LehmanBrothersInternationalEuropeMember
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- Details

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Contracts Accounted for as Credit Derivatives - Narrative (Details) - LBIE vs. AG Financial Products - Positive Outcome of Litigation - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Nov. 28, 2011
Pending Litigation \| AG Financial Products Inc.
Credit Derivatives
Other credit derivative transactions which LBIE owes to AG Financial Products as per calculation of AG financial products		$ 25
Pending Litigation \| Lehman Brothers International (Europe)
Credit Derivatives
Termination payments which AG Financial Products owes to LBIE as per calculation of LBIE		$ 1,400
Settled Litigation \| AG Financial Products Inc.
Credit Derivatives
Litigation settlement, gain	$ 103