Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jul. 31, 2016	Jul. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment	$ 1,232,328	$ 1,115,755
Less: accumulated depreciation and amortization	(415,537)	(415,353)
Property and equipment, net	816,791	700,402
Transportation and other equipment
Property, Plant and Equipment [Line Items]
Property and equipment	85,083	70,133
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment	51,473	44,837
Software
Property, Plant and Equipment [Line Items]
Property and equipment	49,426	65,072
Land
Property, Plant and Equipment [Line Items]
Property and equipment	556,780	481,748
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	$ 489,566	$ 453,965