Segment and Geographic Information - Summary of Revenue by Geographic Area Based on the Shipping Address of the Customers' Location (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Entity Wide Revenue Major Customer [Line Items]
Total revenue	$ 57,017	$ 87,782	$ 80,962
United States
Entity Wide Revenue Major Customer [Line Items]
Total revenue	16,167	46,236	34,231
Reportable Geographical Components | United States
Entity Wide Revenue Major Customer [Line Items]
Total revenue	16,167	46,236	34,231
Reportable Geographical Components | Taiwan
Entity Wide Revenue Major Customer [Line Items]
Total revenue	10,710	0	4,680
Reportable Geographical Components | France
Entity Wide Revenue Major Customer [Line Items]
Total revenue	7,025	12,235	5,812
Reportable Geographical Components | United Kingdom
Entity Wide Revenue Major Customer [Line Items]
Total revenue	6,060	5,974	0
Reportable Geographical Components | Germany
Entity Wide Revenue Major Customer [Line Items]
Total revenue	839	7,393	13,727
Reportable Geographical Components | Rest of World
Entity Wide Revenue Major Customer [Line Items]
Total revenue	$ 16,216	$ 15,944	$ 22,512