FIXED ASSETS - Schedule of Fixed Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Property, Plant and Equipment [Line Items]
Fixed assets, gross	$ 186,195	$ 154,167
Less – accumulated depreciation	(124,802)	(92,134)
Fixed assets, net	61,393	62,033
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Fixed assets, gross	$ 6,436	5,843
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life	7 years
Computer equipment and internal use software
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Fixed assets, gross	$ 135,100	118,974
Computer equipment and internal use software | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Computer equipment and internal use software | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years
Demonstration and spare part units
Property, Plant and Equipment [Line Items]
Fixed assets, gross	$ 28,036	6,860
Demonstration and spare part units | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life	2 years
Demonstration and spare part units | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Fixed assets, gross	$ 16,623	$ 22,490
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life	12 years