SEGMENT AND GEOGRAPHICAL INFORMATION (Segment Reporting) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018 USD ($) country	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) country	Sep. 30, 2017 USD ($)
Segment Reporting [Abstract]
Number of countries in which company operates | country	13		13
Segment Reporting Information [Line Items]
Revenue	$ 151,509	$ 119,819	$ 261,732	$ 233,817
India
Segment Reporting Information [Line Items]
Revenue	31,674	34,689	64,488	66,012
Middle East
Segment Reporting Information [Line Items]
Revenue	30,838	35,891	60,930	72,756
Malaysia
Segment Reporting Information [Line Items]
Revenue	14,652	11,706	28,773	22,513
Argentina
Segment Reporting Information [Line Items]
Revenue	12,489	19,120	28,402	37,267
United States
Segment Reporting Information [Line Items]
Revenue	22,475	0	22,475	0
Australia
Segment Reporting Information [Line Items]
Revenue	8,457	9,315	17,343	17,459
Philippines
Segment Reporting Information [Line Items]
Revenue	13,235	0	13,235	0
Rest of World
Segment Reporting Information [Line Items]
Revenue	$ 17,689	$ 9,098	$ 26,086	$ 17,810