REVENUE Revenue by Type (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)
Revenue from Contract with Customer [Abstract]
Number of reportable segments	1
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 94,364	$ 86,453
Products and solutions net revenues
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	33,267
Subscription services
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	24,868	13,958
Maintenance
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	29,852	31,794
Professional services, training and other services
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 6,377	$ 5,990