Summary of Estimated Useful Lives (Detail)	12 Months Ended
	Apr. 30, 2014
Building and improvements | Minimum
Property Plant And Equipment Estimated Useful Lifes [Line Items]
Estimated useful life	10 years
Building and improvements | Maximum
Property Plant And Equipment Estimated Useful Lifes [Line Items]
Estimated useful life	40 years
Software and hardware | Minimum
Property Plant And Equipment Estimated Useful Lifes [Line Items]
Estimated useful life	3 years
Software and hardware | Maximum
Property Plant And Equipment Estimated Useful Lifes [Line Items]
Estimated useful life	7 years
Machinery and equipment | Minimum
Property Plant And Equipment Estimated Useful Lifes [Line Items]
Estimated useful life	2 years
Machinery and equipment | Maximum
Property Plant And Equipment Estimated Useful Lifes [Line Items]
Estimated useful life	10 years