Property and Equipment - Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 145,676	$ 129,414
Accumulated depreciation and amortization	(87,439)	(81,309)
Total property and equipment, net	58,237	48,105
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	25,882	19,444
Software and Software Development Costs
Property Plant And Equipment [Line Items]
Property and equipment, gross	52,343	50,967
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	29,437	27,435
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 38,014	$ 31,568

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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