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Variable Interest Entities - Unpaid Principal (Details) - Variable Interest Entity, Primary Beneficiary - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
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Financial Guaranty Variable Interest Entities |  |
Variable Interest Entity [Line Items] |  |
FG VIEs’ liabilities with recourse | $ 32 | $ 38
FG VIEs’ liabilities without recourse | 15 | 16
Unpaid principal for FG VIEs’ liabilities with recourse | 182 | 193
Financial Guaranty Variable Interest Entities |  |
Variable Interest Entity [Line Items] |  |
FG VIEs’ assets | 253 | 264
Unpaid principal balance for FG VIEs’ assets that were 90 days or more past due | $ 27 | $ 27

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- Definition Fair Value, Option, Liabilities with Recourse, Unpaid Principal Balance + References No definition available. + Details
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- Definition Fair Value, Option, Loans Held as Liabilities, Aggregate Difference, With Recourse + References No definition available. + Details
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- Definition This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 + Details
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- Definition This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (e)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 + Details
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