Fixed Assets, Net - Components of Fixed Assets, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment
Fixed assets, gross	$ 258,040	$ 244,937
Accumulated depreciation and amortization	(119,919)	(109,181)
Fixed assets, net	138,121	135,756
Leasehold improvements, furniture and fixtures, and other fixed assets
Property, Plant and Equipment
Fixed assets, gross	183,905	184,704
Software, including software development costs
Property, Plant and Equipment
Fixed assets, gross	45,718	32,851
Computer and communications equipment
Property, Plant and Equipment
Fixed assets, gross	$ 28,417	$ 27,382

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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