Equity-Based Compensation Expense Included in Interim Condensed Consolidated Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total equity-based compensation expense	$ 1,565	$ 1,119	$ 4,648	$ 2,795
Cost of revenues
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total equity-based compensation expense	65	34	179	111
Research and development, net
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total equity-based compensation expense	741	438	2,162	1,323
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total equity-based compensation expense	179	151	681	395
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total equity-based compensation expense	$ 580	$ 496	$ 1,626	$ 966