XML 50 R39.htm IDEA: XBRL DOCUMENT v3.22.2

Segment Information - Segment Information (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) segment	Jun. 30, 2021 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment			2
Segment Reporting Information [Line Items]
Segment equity in earnings (losses) of investees	$ 0	$ 34	$ (11)	$ 43
Operating Segments
Segment Reporting Information [Line Items]
Segment equity in earnings (losses) of investees	(34)	48	(35)	67
Segment adjusted operating income (loss)	55	150	188	222
Insurance | Operating Segments
Segment Reporting Information [Line Items]
Revenue, including adjustments	137	180	413	357
Segment revenues	139	182	417	361
Segment expenses	41	47	163	153
Segment equity in earnings (losses) of investees	(34)	48	(35)	67
Less: Segment provision (benefit) for income taxes	9	31	31	44
Segment adjusted operating income (loss)	55	152	188	231
Insurance | Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue, including adjustments	2	2	4	4
Asset Management | Operating Segments
Segment Reporting Information [Line Items]
Revenue, including adjustments	16	19	46	37
Segment revenues	28	21	67	41
Segment expenses	28	24	67	53
Segment equity in earnings (losses) of investees	0	0	0	0
Less: Segment provision (benefit) for income taxes	0	(1)	0	(3)
Segment adjusted operating income (loss)	0	(2)	0	(9)
Asset Management | Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue, including adjustments	$ 12	$ 2	$ 21	$ 4

X

- Definition

Adjusted Income (Loss) Attributable to Parent

+ References

No definition available.

+ Details

Name:	ago_AdjustedIncomeLossAttributabletoParent
Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Revenue, Including Adjustments

+ References

No definition available.

+ Details

Name:	ago_RevenueIncludingAdjustments
Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Segment, Benefits, Losses And Expenses

+ References

No definition available.

+ Details

Name:	ago_SegmentBenefitsLossesAndExpenses
Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Segment, Income Tax Expense (Benefit)

+ References

No definition available.

+ Details

Name:	ago_SegmentIncomeTaxExpenseBenefit
Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Segment Revenue, Including Adjustments

+ References

No definition available.

+ Details

Name:	ago_SegmentRevenueIncludingAdjustments
Namespace Prefix:	ago_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
-URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(f))
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

+ Details

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

X

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

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

X

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=ago_InsuranceSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=ago_AssetManagementSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: