Segment, Geographic and Customer Information - Schedule of Revenue by Country (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Revenue	$ 32,667	$ 25,325	$ 75,882	$ 55,985
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue	32,667	25,325	75,882	55,985
Taiwan | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue	16,126	11,934	34,099	26,830
Hong Kong | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue	9,209	4,442	19,530	11,047
United States | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue	2,263	1,412	5,938	3,880
Other | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue	$ 5,069	$ 7,537	$ 16,315	$ 14,228