FOREIGN CURRENCY DERIVATIVES (Details 4) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Effect of Derivative Contracts on Accumulated Other Comprehensive Income and Statements of Operations [Roll Forward]
Gain (loss) included in AOCI as of beginning of period				$ (1,693)				$ 541	$ (1,693)	$ 541	$ (1,106)
Amount of gain (loss) recognized in OCI (effective portion)									(4,176)	(6,741)	3,095
Net revenues	$ 468,488	$ 501,669	$ 483,069	$ 221,309	$ 216,143	$ 226,534	$ 210,300	$ 203,926	1,674,535	856,903	881,176
Amount of gain (loss) reclassified from OCI into cost of revenues (effective portion)									(980,396)	(417,788)	(439,806)
Interest expense									(83,000)	(29,297)	(29,230)
Total amount of gain (loss) reclassified from AOCI to income (loss) (effective portion)									(1,611)	4,507	(1,448)
Gain (loss) included in AOCI as of end of period	$ (7,480)				$ (1,693)				(7,480)	(1,693)	541
Reclassification out of Accumulated Other Comprehensive Income [Member]
Effect of Derivative Contracts on Accumulated Other Comprehensive Income and Statements of Operations [Roll Forward]
Net revenues									(4,034)	4,715	(4,111)
Amount of gain (loss) reclassified from OCI into cost of revenues (effective portion)									(177)	(208)	2,663
Interest expense									$ 2,600	$ 0	$ 0