XML 89 R69.htm IDEA: XBRL DOCUMENT v3.22.1

Contracts Accounted for as Credit Derivatives - Distribution of Credit Derivative Net Par Outstanding by Internal Rating (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Credit Derivatives
Net Par Outstanding	$ 3,574	$ 4,040
BIG
Credit Derivatives
Net Par Outstanding	60	63
Credit Concentration Risk | Derivative, Aggregate Notional Amount
Credit Derivatives
Net Par Outstanding	$ 3,574	$ 4,040
Percentage of installment premiums denominated in currencies other than the U.S. dollar	100.00%	100.00%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | AAA
Credit Derivatives
Net Par Outstanding	$ 1,359	$ 1,503
Percentage of installment premiums denominated in currencies other than the U.S. dollar	38.00%	37.20%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | AA
Credit Derivatives
Net Par Outstanding	$ 1,217	$ 1,283
Percentage of installment premiums denominated in currencies other than the U.S. dollar	34.10%	31.80%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | A
Credit Derivatives
Net Par Outstanding	$ 407	$ 514
Percentage of installment premiums denominated in currencies other than the U.S. dollar	11.40%	12.70%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | BBB
Credit Derivatives
Net Par Outstanding	$ 531	$ 677
Percentage of installment premiums denominated in currencies other than the U.S. dollar	14.80%	16.70%
Credit Concentration Risk | Derivative, Aggregate Notional Amount | BIG
Credit Derivatives
Net Par Outstanding	$ 60	$ 63
Percentage of installment premiums denominated in currencies other than the U.S. dollar	1.70%	1.60%

X

- Definition

Represents the outstanding principal amounts of the underlying insured obligations that are accounted for as credit derivatives, net of protection purchased.

+ References

No definition available.

+ Details

Name:	ago_FinancialGuarantyContractsAccountedforasCreditDerivativesOutstandingPrincipalAmount
Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9054-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13537-108611

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

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

No definition available.

+ Details

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

X

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_InternalNoninvestmentGradeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CreditConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=ago_DerivativeAggregateNotionalAmountMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=ago_InternalCreditRatingAAAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=ago_InternalCreditRatingAAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=ago_InternalCreditRatingAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=ago_InternalCreditRatingBBBMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: