Stock-based Compensation - Stock-based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Stock-based compensation
Stock-based compensation expense	$ 3,616	$ 3,504	$ 7,124	$ 6,566
Cost of product revenue
Stock-based compensation
Stock-based compensation expense	90		177
Research and development
Stock-based compensation
Stock-based compensation expense	1,254	1,377	2,975	2,513
Selling, general and administrative expense
Stock-based compensation
Stock-based compensation expense	$ 2,272	$ 2,127	$ 3,972	$ 4,053