SEGMENT INFORMATION - Revenue by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenue	$ 360,735	$ 337,443	$ 1,086,520	$ 1,064,308
Europe Caspian
Segment Reporting Information [Line Items]
Revenue	198,439	180,910	596,280	571,598
Africa
Segment Reporting Information [Line Items]
Revenue	48,712	50,516	149,289	156,422
Americas
Segment Reporting Information [Line Items]
Revenue	60,615	53,339	179,822	169,590
Asia Pacific
Segment Reporting Information [Line Items]
Revenue	55,691	52,857	167,421	167,257
Corporate and other
Segment Reporting Information [Line Items]
Revenue	911	2,114	4,126	8,006
External Customer
Segment Reporting Information [Line Items]
Revenue	360,735	337,443	1,086,520	1,064,308
External Customer | Europe Caspian
Segment Reporting Information [Line Items]
Revenue	196,958	179,632	592,280	566,290
External Customer | Africa
Segment Reporting Information [Line Items]
Revenue	48,712	50,516	149,289	156,422
External Customer | Americas
Segment Reporting Information [Line Items]
Revenue	58,468	52,362	173,431	166,651
External Customer | Asia Pacific
Segment Reporting Information [Line Items]
Revenue	55,691	52,857	167,421	167,256
External Customer | Corporate and other
Segment Reporting Information [Line Items]
Revenue	906	2,076	4,099	7,689
Intersegment elimination
Segment Reporting Information [Line Items]
Revenue	3,633	2,293	10,418	8,565
Intersegment elimination | Europe Caspian
Segment Reporting Information [Line Items]
Revenue	1,481	1,278	4,000	5,308
Intersegment elimination | Africa
Segment Reporting Information [Line Items]
Revenue	0	0	0	0
Intersegment elimination | Americas
Segment Reporting Information [Line Items]
Revenue	2,147	977	6,391	2,939
Intersegment elimination | Asia Pacific
Segment Reporting Information [Line Items]
Revenue	0	0	0	1
Intersegment elimination | Corporate and other
Segment Reporting Information [Line Items]
Revenue	$ 5	$ 38	$ 27	$ 317