Restructuring Charges (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Apr. 30, 2016	Oct. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 16.1	$ 16.9
Restructuring and Related Cost, Incurred Cost		13.0
Expense related to lump sum settlement		3.9
Restructuring Reserve	0.0	0.0
Cost of Sales
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	5.7	8.4
Operating Expense
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	10.4	8.5
One-time Termination Benefits | Engine Products
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	8.8	9.2
One-time Termination Benefits | Industrial Products
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	7.3	3.8
One-time Termination Benefits | Corporate & Unallocated
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0.0	3.9
Two Thousand Sixteen Actions | One-time Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost			$ 5.5	$ 7.2
Fiscal Two Thousand Sixteen Third Quarter Actions
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	4.1	0.0
Fiscal Two Thousand Sixteen Fourth Quarter Actions
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	3.5	0.0
Fiscal Two Thousand Sixteen Fourth Quarter Actions | Lease Termination Costs And One-time Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	3.5
Two Thousand Sixteen Actions
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	6.2	0.0
Fiscal Two Thousand Fifteen Actions
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 2.3	$ 16.9