Supplemental Balance Sheet Information (Property, Plant and Equipment) (Details) - USD ($) $ in Millions	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation	$ (744.2)	$ (680.8)
Net property, plant and equipment	484.6	469.8	$ 470.6
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	20.6	20.0
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	292.5	280.4
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	866.8	810.9
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 48.9	$ 39.3