Annual report pursuant to Section 13 and 15(d)

STOCK BASED COMPENSATION - Stock-based Compensation Expense (Details)

v3.20.4
STOCK BASED COMPENSATION - Stock-based Compensation Expense (Details) - USD ($)
$ in Thousands
12 Months Ended
Sep. 28, 2020
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Total stock based compensation expenses $ 1,800 $ 8,006 $ 5,215
Research and development      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Total stock based compensation expenses   3,276 2,713
General and administrative expenses      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Total stock based compensation expenses   3,464 941
Sales and marketing expense      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Total stock based compensation expenses   894 1,373
Cost of sales      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Total stock based compensation expenses   $ 372 $ 188