REVENUE Revenue by Geographic Regions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 79,281	$ 98,701	$ 165,734	$ 202,020
United States
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	32,886	39,951	68,976	79,430
Other Americas
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	5,886	6,960	11,336	13,761
Europe, Middle East and Africa
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	28,706	37,439	61,941	74,592
Asia-Pacific
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 11,803	$ 14,351	$ 23,481	$ 34,237