Goodwill and Other Intangible Assets (Reconciliation of Goodwill) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jul. 31, 2020	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment		$ 0	$ 0	$ 0
Payment to acquire interest in joint venture	$ 7,500,000
Goodwill	316,800,000	316,800,000	238,400,000	238,400,000
Goodwill
Beginning Balance		303,100,000	238,400,000
Goodwill acquired	5,400,000	5,400,000	72,900,000
Currency translation		8,300,000	(8,200,000)
Ending Balance	316,800,000	316,800,000	303,100,000	238,400,000
Goodwill impairment		0	0	0
Engine Products
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	84,800,000	84,800,000	84,500,000	84,900,000
Goodwill
Beginning Balance		84,500,000	84,900,000
Goodwill acquired		0	0
Currency translation		300,000	(400,000)
Ending Balance	84,800,000	84,800,000	84,500,000	84,900,000
Industrial Products
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	232,000,000.0	232,000,000.0	218,600,000	153,500,000
Goodwill
Beginning Balance		218,600,000	153,500,000
Goodwill acquired		5,400,000	72,900,000
Currency translation		8,000,000.0	(7,800,000)
Ending Balance	$ 232,000,000.0	$ 232,000,000.0	$ 218,600,000	$ 153,500,000