Restructuring Charges (Details) - USD ($)	12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	$ 0	$ 16,100,000
Engine Products
Restructuring Cost and Reserve [Line Items]
Restructuring charges		8,800,000
Industrial Products
Restructuring Cost and Reserve [Line Items]
Restructuring charges		7,300,000
Operating expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges		10,400,000
Cost of sales
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 5,700,000