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Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Number of Consolidated FG VIEs (Details) - Variable Interest Entity, Primary Beneficiary - Financial Guaranty Variable Interest Entities - Structured Finance and Other - Entity | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Schedule of Consolidated FG VIEs Rollforward [Roll Forward] |  |  |
Beginning of year | 25 | 25 | 25
Consolidated | 0 | 2 | 1
Deconsolidated | (1) | (2) | (1)
December 31 | 24 | 25 | 25

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