Stockholders' Equity - Non-cash Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 12,883	$ 8,961
Cost of revenues
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	785	558
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	4,081	2,678
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	4,729	3,443
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 3,288	$ 2,282