Fixed Assets, Net - Components of Fixed Assets, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment
Fixed assets, gross	$ 272,924	$ 244,937
Accumulated depreciation and amortization	(124,380)	(109,181)
Fixed assets, net	148,544	135,756
Leasehold improvements, furniture and fixtures, and other fixed assets
Property, Plant and Equipment
Fixed assets, gross	199,557	184,704
Software, including software development costs
Property, Plant and Equipment
Fixed assets, gross	43,687	32,851
Computer and communications equipment
Property, Plant and Equipment
Fixed assets, gross	$ 29,680	$ 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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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