Supplemental Balance Sheet Information (Property, Plant and Equipment) (Details) - USD ($) $ in Millions	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation	$ (790.4)	$ (744.2)
Net property, plant and equipment	509.3	484.6	$ 469.8
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	22.8	20.6
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	310.8	292.5
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	769.1	742.9
Computer software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	132.6	123.9
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 64.4	$ 48.9