Financial Guaranty Variable Interest Entities and Consolidated Investment Vehicles - Roll Forward of Number of Consolidated CIVs (Details) - Consolidated Investment Vehicles $ in Millions	6 Months Ended
	Jun. 30, 2022 USD ($) consolidatedInvestmentVehicle	Jun. 30, 2022 USD ($) fund	Jun. 30, 2022 USD ($) Entity	Jun. 30, 2021 Entity fund
CLO Warehouse
Variable Interest Entity [Line Items]
Number of financial assets securitized | fund		2		2
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Beginning of year	20		20	11
Consolidated			2	5
Deconsolidated (1)			(1)	(1)
June 30,	21		21	15
Deconsolidation, net assets | $	$ 417	$ 417	$ 417