GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Cost	$ 1,091,766	$ 1,090,656
Accumulated Amortization	(507,510)	(440,138)
Net	584,256	650,518
Developed technology
Finite-Lived Intangible Assets [Line Items]
Cost	245,850	242,259
Accumulated Amortization	(186,356)	(168,289)
Net	59,494	73,970
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Cost	770,696	772,969
Accumulated Amortization	(261,595)	(218,043)
Net	509,101	554,926
Distributor relationships and technology licenses
Finite-Lived Intangible Assets [Line Items]
Cost	6,843	6,882
Accumulated Amortization	(6,104)	(5,237)
Net	739	1,645
Definite-lived trademark and trade name
Finite-Lived Intangible Assets [Line Items]
Cost	39,205	39,304
Accumulated Amortization	(24,894)	(20,586)
Net	14,311	18,718
Core technology
Finite-Lived Intangible Assets [Line Items]
Cost	7,192	7,192
Accumulated Amortization	(7,016)	(6,845)
Net	176	347
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	292	292
Accumulated Amortization	(292)	(292)
Net	0	0
Leasehold interest
Finite-Lived Intangible Assets [Line Items]
Cost	500	500
Accumulated Amortization	(500)	(500)
Net	0	0
Backlog
Finite-Lived Intangible Assets [Line Items]
Cost	16,327	16,397
Accumulated Amortization	(16,327)	(16,397)
Net	0	0
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Cost	3,317	3,317
Accumulated Amortization	(3,152)	(2,690)
Net	165	627
Other
Finite-Lived Intangible Assets [Line Items]
Cost	1,208	1,208
Accumulated Amortization	(938)	(923)
Net	$ 270	$ 285