XML 134 R107.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Roll Forward of Number of Consolidated CIVs (Details) (Details) - Variable Interest Entity, Primary Beneficiary - Consolidated investment vehicles | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 entity | Dec. 31, 2023 entity | Dec. 31, 2022 fund entity | Dec. 31, 2021 entity
Variable Interest Entity [Line Items] |  |  |  |
Number of financial assets securitized | fund |  |  | 2 |
Schedule of Consolidated FG VIEs Rollforward [Roll Forward] |  |  |  |
Consolidated | 0 | 0 | 4 |
Deconsolidated | (1) | (19) | (2) |
December 31 | 2 | 3 | 22 | 20

X
- Definition Number Of Financial Assets Securitized + References No definition available. + Details
Name: | ago_NumberOfFinancialAssetsSecuritized
Namespace Prefix: | ago_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of Consolidated FG VIEs Rollforward [Roll Forward] + References No definition available. + Details
Name: | ago_ScheduleofConsolidatedFGVIEsRollforwardRollForward
Namespace Prefix: | ago_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Variable Interest Entities, Number of Entities Consolidated in the Period + References No definition available. + Details
Name: | ago_VariableInterestEntitiesNumberofEntitiesConsolidatedinthePeriod
Namespace Prefix: | ago_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Variable Interest Entities, Number of Entities Deconsolidated in the Period + References No definition available. + Details
Name: | ago_VariableInterestEntitiesNumberofEntitiesDeconsolidatedinthePeriod
Namespace Prefix: | ago_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Variable Interest Entity, Number of Entities Consolidated + References No definition available. + Details
Name: | ago_VariableInterestEntityNumberofEntitiesConsolidated
Namespace Prefix: | ago_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- 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 810 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481203/810-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 810 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 25 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481231/810-10-45-25 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 810 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (bb) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481203/810-10-50-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 810 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 25 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481231/810-10-45-25 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b)(1)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A + Details
Name: | us-gaap_VariableInterestEntityLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_ConsolidatedEntitiesAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=ago_ConsolidatedInvestmentVehiclesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |