REVENUE RECOGNITION - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation Of Revenue [Line Items]
Backlog associated with committed purchase orders from customers	$ 11,800		$ 11,800
Cumulative catch-up adjustment arising from changes in estimates of transaction price, net			9,854	$ 1,458
Unbilled receivables increase			$ 17,062	$ 13,494
Revenue from Contracts with Customers - ASU No. 2014-09 [Member]
Disaggregation Of Revenue [Line Items]
Percentage of revenue recorded from sales of materials	97.00%	97.00%	97.00%	96.00%
Revenue from Contracts with Customers - ASU No. 2014-09 [Member] | Adesis, Inc. [Member]
Disaggregation Of Revenue [Line Items]
Percentage of revenue recorded from provision of services	3.00%	3.00%	3.00%	4.00%