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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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