Segment Reporting (Summary Of Segment Detail) (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 31, 2019	Oct. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 672.7	$ 701.4
Earnings before income taxes	86.6	96.4
Engine Products segment
Segment Reporting Information [Line Items]
Net sales	459.2	480.9
Industrial Products segment
Segment Reporting Information [Line Items]
Net sales	213.5	220.5
Operating Segments \| Engine Products segment
Segment Reporting Information [Line Items]
Earnings before income taxes	62.4	63.9
Operating Segments \| Industrial Products segment
Segment Reporting Information [Line Items]
Earnings before income taxes	29.5	36.6
Corporate and Unallocated
Segment Reporting Information [Line Items]
Earnings before income taxes	(5.3)	(4.1)
Off-Road \| Engine Products segment
Segment Reporting Information [Line Items]
Net sales	68.6	76.2
On-Road \| Engine Products segment
Segment Reporting Information [Line Items]
Net sales	40.7	45.9
Aftermarket \| Engine Products segment
Segment Reporting Information [Line Items]
Net sales	319.4	331.2
Aerospace and Defense \| Engine Products segment
Segment Reporting Information [Line Items]
Net sales	30.5	27.6
Industrial Filtration Solutions \| Industrial Products segment
Segment Reporting Information [Line Items]
Net sales	149.0	149.4
Gas Turbine Systems \| Industrial Products segment
Segment Reporting Information [Line Items]
Net sales	20.7	25.5
Special Applications \| Industrial Products segment
Segment Reporting Information [Line Items]
Net sales	$ 43.8	$ 45.6

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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