Property and Equipment - Net - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 63,048	$ 62,353
Less accumulated depreciation	(45,360)	(43,646)
Property and equipment, net	17,688	18,707
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	27,428	27,294
Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	31,978	27,422
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	1,620	1,618
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	1,244	1,256
Work in Process (Primarily Software Development Costs) [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	599	4,584
Other [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 179	$ 179

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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