GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Mar. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Cost	$ 1,174,945	$ 1,170,562
Accumulated Amortization	(287,200)	(257,893)
Net	887,745	912,669
Developed technology
Finite-Lived Intangible Assets [Line Items]
Cost	254,895	254,005
Accumulated Amortization	(119,732)	(110,200)
Net	135,163	143,805
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Cost	834,833	831,731
Accumulated Amortization	(122,064)	(105,319)
Net	712,769	726,412
Distributor relationships and technology licenses
Finite-Lived Intangible Assets [Line Items]
Cost	8,343	8,290
Accumulated Amortization	(3,603)	(3,068)
Net	4,740	5,222
Definite-lived trademark and trade name
Finite-Lived Intangible Assets [Line Items]
Cost	43,951	43,817
Accumulated Amortization	(13,898)	(12,078)
Net	30,053	31,739
Core technology
Finite-Lived Intangible Assets [Line Items]
Cost	7,164	7,108
Accumulated Amortization	(6,181)	(6,009)
Net	983	1,099
Net beneficial leases
Finite-Lived Intangible Assets [Line Items]
Cost	336	336
Accumulated Amortization	(336)	(336)
Net	0	0
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Cost	287	278
Accumulated Amortization	(287)	(278)
Net	0	0
Leasehold interest
Finite-Lived Intangible Assets [Line Items]
Cost	2,600	2,600
Accumulated Amortization	(1,143)	(998)
Net	1,457	1,602
Backlog
Finite-Lived Intangible Assets [Line Items]
Cost	18,236	18,142
Accumulated Amortization	(18,230)	(18,133)
Net	6	9
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Cost	3,092	3,047
Accumulated Amortization	(839)	(594)
Net	2,253	2,453
Other
Finite-Lived Intangible Assets [Line Items]
Cost	1,208	1,208
Accumulated Amortization	(887)	(880)
Net	$ 321	$ 328