Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 68,663	$ 66,924
Less accumulated depreciation	(50,760)	(44,199)
Property and equipment, net	17,903	22,725
Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	39,250	38,373
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	5,051	5,017
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 24,362	$ 23,534

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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