Revenue Recognition - Summary of Revenues Disaggregated by Geography (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation Of Revenue [Line Items]
Total revenue		$ 24,462	$ 35,471	$ 74,688	$ 105,806
UNITED STATES
Disaggregation Of Revenue [Line Items]
Total revenue		15,006	21,613	42,269	63,219
Other
Disaggregation Of Revenue [Line Items]
Total revenue	[1]	$ 9,456	$ 13,858	$ 32,419	$ 42,587

[1] No single country outside of the United States represented 10% or more of the Company’s revenues in the periods presented.