SEGMENTS INFORMATION (Revenues by Customer Location) (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	$ 632,383	$ 551,587	$ 1,283,742	$ 1,072,920
United States
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	365,004	318,988	735,093	618,668
United Kingdom
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	82,277	69,042	174,409	134,781
Switzerland
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	46,537	35,364	93,759	71,597
Netherlands
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	27,237	21,039	53,146	41,655
Russia
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	19,448	22,460	41,409	38,352
Germany
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	19,798	19,622	39,991	38,776
Canada
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	16,585	15,785	34,505	32,757
Other locations
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 55,497	$ 49,287	$ 111,430	$ 96,334