Property and Equipment - Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 157,614	$ 145,676
Accumulated depreciation and amortization	(95,180)	(87,439)
Total property and equipment, net	62,434	58,237
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	35,683	25,882
Software and Software Development Costs
Property Plant And Equipment [Line Items]
Property and equipment, gross	53,001	52,343
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	28,772	29,437
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 40,158	$ 38,014

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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