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Outstanding Exposure - BIG Net Par Outstanding (Details) $ in Millions | Mar. 31, 2024 USD ($) risk | Dec. 31, 2023 USD ($) risk
--- | --- | ---
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, credit derivative | $ 3,421 | $ 3,608
Net | 248,144 | 249,153
BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | 5,141 | 5,383
Net par outstanding, credit derivative | 52 | 54
Net | $ 5,193 | $ 5,437
Number of risks, financial guaranty insurance | risk | 212 | 217
Number of risks, credit derivative | risk | 11 | 11
Number of risks | risk | 223 | 228
BIG | BIG 1 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | $ 2,356 | $ 2,394
Net par outstanding, credit derivative | 15 | 16
Net | $ 2,371 | $ 2,410
Number of risks, financial guaranty insurance | risk | 91 | 95
Number of risks, credit derivative | risk | 2 | 2
Number of risks | risk | 93 | 97
BIG | BIG 2 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | $ 977 | $ 979
Net par outstanding, credit derivative | 10 | 10
Net | $ 987 | $ 989
Number of risks, financial guaranty insurance | risk | 12 | 13
Number of risks, credit derivative | risk | 2 | 2
Number of risks | risk | 14 | 15
BIG | BIG 3 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | $ 1,808 | $ 2,010
Net par outstanding, credit derivative | 27 | 28
Net | $ 1,835 | $ 2,038
Number of risks, financial guaranty insurance | risk | 109 | 109
Number of risks, credit derivative | risk | 7 | 7
Number of risks | risk | 116 | 116

X
- Definition Represents the number of unique credits in the insured portfolio accounted for as credit derivative. + References No definition available. + Details
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Namespace Prefix: | ago_
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- 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
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- Definition Represents the outstanding principal amounts of the underlying insured obligations for financial guaranty contracts, after netting out ceded contracts. + References No definition available. + Details
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- Definition This element represents the amount of insured contractual payments outstanding attributable to the principal of the underlying insured obligations for financial guaranty insurance contracts presented in the context of each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guaranty insurance contracts, before adjusting for the effect of consolidating VIEs. + References No definition available. + Details
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- Definition This element represents the number of issued and outstanding contracts for each surveillance grouping or category used by management to monitor and track potential deterioration in the credit worthiness of the insured party's ability to meet its financial obligations related to the contracts underlying financial guarantee insurance contracts the entity has issued. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 32 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480046/944-40-55-32 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 9 -Subparagraph (a)(5)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-9 + Details
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