Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Oct. 31, 2018	Jul. 31, 2018
Property, Plant and Equipment [Line Items]
Total cost	$ 755,136	$ 723,531
Less accumulated depreciation	(211,439)	(201,477)
Net property, plant and equipment	543,697	522,054
Land
Property, Plant and Equipment [Line Items]
Total cost	61,738	57,413
Building and Building Improvements
Property, Plant and Equipment [Line Items]
Total cost	487,865	468,824
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Total cost	$ 205,533	$ 197,294