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Contracts Accounted for as Financial Guaranty Insurance - Net Earned Premiums (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2026 | Mar. 31, 2025
Insurance [Abstract] |  |
Scheduled net earned premiums | $ 76 | $ 76
Accelerations from refundings, terminations and modifications | (6) | 5
Accretion of discount on net premiums receivable | 10 | 9
FG insurance net earned premiums | 80 | 90
Specialty net earned premiums | 2 | 1
Net earned premiums | $ 82 | $ 91

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- Definition Financial Guarantee Insurance Contracts, Accelerated Premium Revenue (Refunds), Amount + References No definition available. + Details
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- Definition This element represents the accretion of the discount for premiums receivable, net of ceded contracts, on financial guaranty insurance contracts. + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts, Premiums Earned, Net + References No definition available. + Details
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- Definition Represents the amount of premium revenue on financial guaranty insurance contracts recognized during the period, excluding acceleration of premium earnings and accretion of discount on net premium receivable. + References No definition available. + Details
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- Definition Premiums Earned, Net, Specialty Insurance and Reinsurance + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-14 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-11 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-15 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-12 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479838/944-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 11 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-11 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 235 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column E)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477965/944-235-S99-2 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(c)) -SubTopic 220 -Topic 942 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(1)) -SubTopic 220 -Topic 944 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
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