STOCKHOLDERS' EQUITY 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 Payment Arrangement, Expense	$ 3,514	$ 3,297	$ 10,216	$ 8,132
Restricted Stock Units (RSUs) [Member] | Time Based RSUs
Employee Benefits and Share-based Compensation	2,507	2,515	7,528	6,032
Restricted Stock Units (RSUs) [Member] | Performance-Based Vesting [Member]
Employee Benefits and Share-based Compensation	977	756	2,599	2,021
Employee Stock
Employee Benefits and Share-based Compensation	30	26	89	79
Cost of Products Revenues [Member]
Share-based Payment Arrangement, Expense	132	150	423	370
Cost of Services Revenues [Member]
Share-based Payment Arrangement, Expense	311	283	938	539
Research and Development Expense [Member]
Share-based Payment Arrangement, Expense	340	546	1,270	1,199
Selling and Marketing Expense [Member]
Share-based Payment Arrangement, Expense	639	739	1,858	1,761
General and Administrative Expense [Member]
Share-based Payment Arrangement, Expense	$ 2,092	$ 1,579	$ 5,727	$ 4,263