Stock Based Compensation Expense - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 541	$ 465	$ 1,448	$ 1,175
Cost of Sales
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	50	48	157	117
Selling, General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	368	291	909	744
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 123	$ 126	$ 382	$ 314