Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 19,537	$ 17,820
Less accumulated depreciation and amortization	(14,301)	(12,603)
Property and equipment, net	5,236	5,217
Computer equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,335	1,329
Capitalized software
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,322	1,518
Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	8,737	6,973
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 8,143	$ 8,000

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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