Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Apr. 30, 2016	Apr. 30, 2015
Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets, Gross Carrying Amount	$ 81,066	$ 81,268
Finite lived intangible assets, Accumulated Amortization	(18,575)	(7,950)
Finite lived intangible assets, Net Carrying Amount	62,491	73,318
Intangible assets, Gross Carrying Amount	81,499	81,718
Intangible assets, Net Carrying Amount	62,924	73,768
Patents in progress
Finite-Lived Intangible Assets [Line Items]
Deposits on patents	433	450
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets, Gross Carrying Amount	28,560	28,260
Finite lived intangible assets, Accumulated Amortization	(6,423)	(1,633)
Finite lived intangible assets, Net Carrying Amount	22,137	26,627
Developed technology
Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets, Gross Carrying Amount	16,430	16,630
Finite lived intangible assets, Accumulated Amortization	(2,890)	(1,014)
Finite lived intangible assets, Net Carrying Amount	13,540	15,616
Patents, trademarks, and trade names
Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets, Gross Carrying Amount	36,076	36,378
Finite lived intangible assets, Accumulated Amortization	(9,262)	(5,303)
Finite lived intangible assets, Net Carrying Amount	$ 26,814	$ 31,075