Segment Reporting (Summary Of Segment Detail) (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Segment Reporting Information [Line Items]
Net sales	$ 2,844.9	$ 2,734.2	$ 2,371.9
Equity earnings in unconsolidated affiliates	2.2	3.6	5.0
Earnings (loss) before income taxes	375.2	363.6	322.0
Equity investments in unconsolidated affiliates	23.0	21.7	19.0
Engine Products
Segment Reporting Information [Line Items]
Net sales	1,926.0	1,849.0	1,553.3
Industrial Products
Segment Reporting Information [Line Items]
Net sales	918.9	885.2	818.6
Operating Segments \| Engine Products
Segment Reporting Information [Line Items]
Net sales	1,926.0	1,849.0	1,553.3
Equity earnings in unconsolidated affiliates	2.1	3.7	4.4
Earnings (loss) before income taxes	254.6	258.8	218.4
Equity investments in unconsolidated affiliates	19.0	17.8	14.8
Operating Segments \| Industrial Products
Segment Reporting Information [Line Items]
Net sales	918.9	885.2	818.6
Equity earnings in unconsolidated affiliates	0.1	(0.1)	0.6
Earnings (loss) before income taxes	140.1	135.5	128.5
Equity investments in unconsolidated affiliates	4.0	3.9	4.2
Corporate and Unallocated
Segment Reporting Information [Line Items]
Earnings (loss) before income taxes	$ (19.5)	$ (30.7)	$ (24.9)

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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