XML 81 R61.htm IDEA: XBRL DOCUMENT
v3.23.1

Contracts Accounted for as Insurance - Expected Future Premium Collections and Earnings (Details) $ in Millions | Mar. 31, 2023 USD ($)
--- | ---
Consolidated Entity Excluding Variable Interest Entities (VIE) |
Future Premiums to be Collected [Abstract] |
2023 (April 1 - June 30) | $ 32
2023 (July 1 - September 30) | 38
2023 (October 1 - December 31) | 19
Subtotal 2023 | 89
2024 | 111
2025 | 96
2026 | 94
2027 | 91
2028-2032 | 379
2033-2037 | 252
2038-2042 | 175
After 2042 | 364
Total | 1,651
Financial Guarantee Insurance Product Line |
Future Net Premiums to be Earned [Abstract] |
2023 (April 1 - June 30) | 70
2023 (July 1 - September 30) | 70
2023 (October 1 - December 31) | 69
Subtotal 2023 | 209
2024 | 267
2025 | 251
2026 | 235
2027 | 221
2028-2032 | 925
2033-2037 | 618
2038-2042 | 377
After 2042 | 528
Total | 3,631
Future accretion | 307
Total future net earned premiums | $ 3,938

X
- Definition For financial guarantee insurance contracts, the discounted amount of premium revenue expected to be recognized over the term of the contract period. + References No definition available. + Details
Name: | ago_FinancialGuaranteeInsuranceContractsFutureExpectedAccretiononNetEarnedPremium
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition For financial guarantee insurance contracts, the undiscounted amount of premium revenue expected to be recognized over the term of the contract period. + References No definition available. + Details
Name: | ago_FinancialGuaranteeInsuranceContractsFutureExpectedNetEarnedPremiumtobeRecognized
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Financial Guarantee Insurance Contracts, Future Expected Premium Revenue to be Recognized, Fiscal Year + References No definition available. + Details
Name: | ago_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedFiscalYear
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition For financial guarantee insurance contracts, the amount of premium revenue expected to be recognized beyond the twentieth year following the statement of financial position reporting date. + References No definition available. + Details
Name: | ago_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenuetobeRecognizedBeyondYear20
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition For financial guarantee insurance contracts, the aggregate amount of premium related to the premium receivable which is expected to be collected beyond the twentieth year following the statement of financial position reporting date. + References No definition available. + Details
Name: | ago_FinancialGuaranteeInsuranceContractsPremiumReceivablePremiumExpectedtobeCollectedBeyondYear20
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unearned premium revenue in the statement of financial position for financial guaranty insurance contracts, net of the unexpired portion of premiums ceded and before adjustment for loss claims paid but not yet expensed. + References No definition available. + Details
Name: | ago_FinancialGuaranteeInsuranceContractsUnearnedPremiumRevenueExcludingClaimsPaidNotYetExpensedNet
Namespace Prefix: | ago_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Future Net Premiums to be Earned + References No definition available. + Details
Name: | ago_FutureNetPremiumsToBeEarnedAbstract
Namespace Prefix: | ago_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Future Premiums to be Collected + References No definition available. + Details
Name: | ago_FuturePremiumsToBeCollectedAbstract
Namespace Prefix: | ago_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in fourth fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFourthQuarterFollowingBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in second fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringSecondQuarterFollowingBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in third fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringThirdQuarterFollowingBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in eleventh through fifteenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(2) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan10AndWithin15YearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in sixteenth through twentieth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(2) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan15AndWithin20YearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(2) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFiveAndWithin10YearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanOneAndWithinTwoYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanThreeAndWithinFourYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanTwoAndWithinThreeYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in fourth fiscal quarter following current year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFourthQuarterFollowingBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in second fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringSecondQuarterFollowingTheBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in third fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringThirdQuarterFollowingBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in eleventh through fifteenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan10AndWithin15YearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in sixteenth through twentieth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan15AndWithin20YearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFiveAndWithin10YearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanOneAndWithinTwoYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanThreeAndWithinFourYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References 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 https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanTwoAndWithinThreeYearsFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivable under financial guarantee insurance contract to be collected in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=6933075&loc=SL5748726-161290 + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedWithinOneYearFromBalanceSheetDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of premium receivables under financial guarantee insurance contracts. + References No definition available. + Details
Name: | us-gaap_FinancialGuaranteeInsuranceContractsPremiumReceivablePremiumExpectedToBeCollected
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_FinancialGuaranteeInsuranceSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |