Information about Geographic Areas - Classification of Revenue by Geography (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 30,604	$ 28,616	$ 88,637	$ 76,700
Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	21,730	21,032	63,235	53,865
Europe & Middle East
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	7,128	6,110	20,636	18,260
Asia Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 1,746	$ 1,474	$ 4,766	$ 4,575