Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 63,673	$ 62,800
Less accumulated depreciation	(49,355)	(47,307)
Property and equipment, net	14,318	15,493
Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	39,633	39,644
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	4,610	4,662
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 19,430	$ 18,494

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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