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v3.26.1

Outstanding Exposure - BIG Net Par Outstanding (Details) $ in Millions | Mar. 31, 2026 USD ($) risk | Dec. 31, 2025 USD ($) risk
--- | --- | ---
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, credit derivative | $ 3,300 | $ 3,800
Net | 278,600 | 277,100
BIG |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | 8,610 | 8,730
Net par outstanding, credit derivative | 30 | 30
Net | $ 8,640 | $ 8,760
Number of risks, financial guaranty insurance | risk | 192 | 195
Number of risks, credit derivative | risk | 7 | 7
Number of risks | risk | 199 | 202
BIG | BIG 1 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | $ 3,600 | $ 3,710
Net par outstanding, credit derivative | 30 | 30
Net | $ 3,630 | $ 3,740
Number of risks, financial guaranty insurance | risk | 86 | 87
Number of risks, credit derivative | risk | 3 | 3
Number of risks | risk | 89 | 90
BIG | BIG 2 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | $ 3,830 | $ 3,810
Net par outstanding, credit derivative | 0 | 0
Net | $ 3,830 | $ 3,810
Number of risks, financial guaranty insurance | risk | 14 | 13
Number of risks, credit derivative | risk | 1 | 1
Number of risks | risk | 15 | 14
BIG | BIG 3 |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Net par outstanding, financial guaranty insurance | $ 1,180 | $ 1,210
Net par outstanding, credit derivative | 0 | 0
Net | $ 1,180 | $ 1,210
Number of risks, financial guaranty insurance | risk | 92 | 95
Number of risks, credit derivative | risk | 3 | 3
Number of risks | risk | 95 | 98

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- 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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- 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://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 34 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-34 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -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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