GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Mar. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Cost	$ 1,090,694	$ 1,192,226
Accumulated Amortization	(415,531)	(379,452)
Net	675,163	812,774
Developed technology
Finite-Lived Intangible Assets [Line Items]
Cost	242,270	259,758
Accumulated Amortization	(160,816)	(148,937)
Net	81,454	110,821
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Cost	773,004	845,490
Accumulated Amortization	(202,940)	(176,425)
Net	570,064	669,065
Distributor relationships and technology licenses
Finite-Lived Intangible Assets [Line Items]
Cost	6,882	9,019
Accumulated Amortization	(4,880)	(5,389)
Net	2,002	3,630
Definite-lived trademark and trade name
Finite-Lived Intangible Assets [Line Items]
Cost	39,303	44,387
Accumulated Amortization	(19,267)	(18,138)
Net	20,036	26,249
Core technology
Finite-Lived Intangible Assets [Line Items]
Cost	7,200	7,345
Accumulated Amortization	(6,781)	(6,712)
Net	419	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	293	317
Accumulated Amortization	(293)	(317)
Net	0	0
Leasehold interest
Finite-Lived Intangible Assets [Line Items]
Cost	500	2,600
Accumulated Amortization	(500)	(2,130)
Net	0	470
Backlog
Finite-Lived Intangible Assets [Line Items]
Cost	16,383	18,544
Accumulated Amortization	(16,383)	(18,544)
Net	0	0
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Cost	3,315	3,183
Accumulated Amortization	(2,417)	(1,621)
Net	898	1,562
Other
Finite-Lived Intangible Assets [Line Items]
Cost	1,208	1,247
Accumulated Amortization	(918)	(903)
Net	$ 290	$ 344