REVENUE RECOGNITION - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Contract expiration year									2022
Backlog associated with committed purchase orders from customers	$ 6,500								$ 6,500
Cumulative effect adjustment to reduction of retained earnings											$ (17,100)
Revenue	$ 101,729	$ 97,515	$ 118,168	$ 87,765	$ 70,143	$ 77,550	$ 56,149	$ 43,572	$ 405,177	$ 247,414	$ 335,629
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%	95.00%	97.00%
Cumulative effect adjustment to reduction of retained earnings					$ (17,100)					$ (17,100)
Revenue										$ 78,900
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%	5.00%	3.00%