Supplemental Balance Sheet Information (Property, Plant and Equipment) (Details) - USD ($) $ in Millions	Jan. 31, 2019	Jul. 31, 2018
Property, Plant and Equipment [Line Items]
Less: accumulated depreciation	$ (821.3)	$ (790.4)
Property, plant and equipment, net	552.5	509.3
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	24.4	22.8
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	315.2	310.8
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	793.5	769.1
Computer software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	140.3	132.6
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 100.4	$ 64.4