Stock-based Compensation - Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 1,837	$ 1,129
Cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	83	72
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	762	435
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	186	82
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 806	$ 540