Stock-based Compensation - Summary Components of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 5,023	$ 4,620	$ 3,610
Cost of Services [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	559	525	203
Cost of Product Sales [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	44	45	53
Selling, General and Administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	4,082	3,655	3,135
Product Development [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 338	$ 395	$ 219