GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Cost	$ 1,110,944	$ 1,192,226
Accumulated Amortization	(373,126)	(379,452)
Net	737,818	812,774
Developed technology
Finite-Lived Intangible Assets [Line Items]
Cost	243,961	259,758
Accumulated Amortization	(146,123)	(148,937)
Net	97,838	110,821
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Cost	784,361	845,490
Accumulated Amortization	(172,969)	(176,425)
Net	611,392	669,065
Distributor relationships and technology licenses
Finite-Lived Intangible Assets [Line Items]
Cost	8,909	9,019
Accumulated Amortization	(5,802)	(5,389)
Net	3,107	3,630
Definite-lived trademark and trade name
Finite-Lived Intangible Assets [Line Items]
Cost	40,514	44,387
Accumulated Amortization	(17,376)	(18,138)
Net	23,138	26,249
Core technology
Finite-Lived Intangible Assets [Line Items]
Cost	7,228	7,345
Accumulated Amortization	(6,667)	(6,712)
Net	561	633
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	298	317
Accumulated Amortization	(298)	(317)
Net	0	0
Leasehold interest
Finite-Lived Intangible Assets [Line Items]
Cost	2,600	2,600
Accumulated Amortization	(2,415)	(2,130)
Net	185	470
Backlog
Finite-Lived Intangible Assets [Line Items]
Cost	18,346	18,544
Accumulated Amortization	(18,346)	(18,544)
Net	0	0
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Cost	3,183	3,183
Accumulated Amortization	(1,887)	(1,621)
Net	1,296	1,562
Other
Finite-Lived Intangible Assets [Line Items]
Cost	1,208	1,247
Accumulated Amortization	(907)	(903)
Net	$ 301	$ 344