Fixed Assets, Net - Components of Fixed Assets, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment
Fixed assets, gross	$ 184,953	$ 170,773
Accumulated depreciation and amortization	(82,937)	(72,757)
Fixed assets, net	102,016	98,016
Leasehold improvements and other fixed assets
Property, Plant and Equipment
Fixed assets, gross	129,244	119,682
Software, including software development costs
Property, Plant and Equipment
Fixed assets, gross	29,953	28,063
Computer and communications equipment
Property, Plant and Equipment
Fixed assets, gross	$ 25,756	$ 23,028

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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