Other Financial Statement Information - Schedule of Revenue by geography (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues	$ 75,289	$ 61,207	$ 55,819	$ 53,578	$ 50,554	$ 36,607	$ 31,744	$ 27,408	$ 245,893	$ 146,313	$ 71,085
North America [Member]
Revenues									139,758	85,132	43,622
Europe, Middle East and Africa [Member]
Revenues									58,004	35,812	18,602
China [Member]
Revenues									29,920	15,075	3,171
Asia Pacific [Member]
Revenues									$ 18,211	$ 10,294	$ 5,690