Information about Geographic Areas - Classification of Revenue by Geography (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 27,016	$ 23,933	$ 79,672	$ 61,257
Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	20,060	16,784	59,612	43,188
Europe & Middle East
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	4,911	4,934	14,564	12,667
Asia Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 2,045	$ 2,215	$ 5,496	$ 5,402