Segment Reporting (Summary of Segment Detail) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Segment Reporting Information
Net sales	$ 629.7	$ 712.8	$ 1,964.4	$ 2,117.9
Earnings before income taxes	84.4	99.5	253.9	276.4
Operating Segments \| Engine Products segment
Segment Reporting Information
Net sales	420.4	489.4	1,315.2	1,439.3
Earnings before income taxes	56.5	71.5	172.2	188.6
Operating Segments \| Engine Products segment \| Off-Road
Segment Reporting Information
Net sales	63.5	84.8	199.6	240.0
Operating Segments \| Engine Products segment \| On-Road
Segment Reporting Information
Net sales	25.1	46.9	99.5	135.6
Operating Segments \| Engine Products segment \| Aftermarket
Segment Reporting Information
Net sales	301.9	327.7	929.4	980.0
Operating Segments \| Engine Products segment \| Aerospace and Defense
Segment Reporting Information
Net sales	29.9	30.0	86.7	83.7
Operating Segments \| Industrial Products segment
Segment Reporting Information
Net sales	209.3	223.4	649.2	678.6
Earnings before income taxes	34.7	32.7	98.8	101.5
Operating Segments \| Industrial Products segment \| Industrial Filtration Solutions
Segment Reporting Information
Net sales	137.4	155.2	441.4	469.2
Operating Segments \| Industrial Products segment \| Gas Turbine Systems
Segment Reporting Information
Net sales	29.2	27.5	74.2	80.5
Operating Segments \| Industrial Products segment \| Special Applications
Segment Reporting Information
Net sales	42.7	40.7	133.6	128.9
Corporate and Unallocated
Segment Reporting Information
Earnings before income taxes	$ (6.8)	$ (4.7)	$ (17.1)	$ (13.7)

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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