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Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Unpaid Principal (Details) - Variable Interest Entity, Primary Beneficiary - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
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Financial Guaranty Variable Interest Entities |  |
Variable Interest Entity [Line Items] |  |
FG VIEs’ liabilities with recourse | $ 31 | $ 25
FG VIEs’ liabilities without recourse | 16 | 16
Unpaid principal for FG VIEs’ liabilities with recourse | 420 | 568
Financial Guaranty Variable Interest Entities |  |
Variable Interest Entity [Line Items] |  |
FG VIEs’ assets | 260 | 259
Unpaid principal balance for FG VIEs’ assets that were 90 days or more past due | $ 27 | $ 29

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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://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -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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