GOODWILL AND INTANGIBLE ASSETS - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Cost	$ 1,101,973	$ 1,091,953
Accumulated Amortization	(551,096)	(528,374)
Net	550,877	563,579
Developed technology
Finite-Lived Intangible Assets [Line Items]
Cost	250,858	249,675
Accumulated Amortization	(197,510)	(191,876)
Net	53,348	57,799
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Cost	771,578	767,366
Accumulated Amortization	(290,570)	(275,361)
Net	481,008	492,005
Distributor relationships and technology licenses
Finite-Lived Intangible Assets [Line Items]
Cost	11,095	6,785
Accumulated Amortization	(6,640)	(6,321)
Net	4,455	464
Definite-lived trademark and trade name
Finite-Lived Intangible Assets [Line Items]
Cost	39,243	39,059
Accumulated Amortization	(27,610)	(26,246)
Net	11,633	12,813
Core technology
Finite-Lived Intangible Assets [Line Items]
Cost	7,192	7,192
Accumulated Amortization	(7,103)	(7,074)
Net	89	118
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	16,354	16,223
Accumulated Amortization	(16,354)	(16,223)
Net	0	0
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Cost	3,317	3,317
Accumulated Amortization	(3,233)	(3,202)
Net	84	115
Other
Finite-Lived Intangible Assets [Line Items]
Cost	1,208	1,208
Accumulated Amortization	(948)	(943)
Net	$ 260	$ 265