Property, Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2014	Jul. 31, 2014
Property, Plant and Equipment [Line Items]
Land	$ 23,464	$ 21,592
Buildings and improvements	180,779	175,611
Machinery and equipment	75,153	76,298
Total cost	279,396	273,501
Less accumulated depreciation	(104,732)	(103,639)
Property, plant and equipment, net	$ 174,664	$ 169,862