Segment Reporting (Summary Of Segment Detail) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017
Segment Reporting Information [Line Items]
Net sales	$ 700.0	$ 608.2	$ 2,009.5	$ 1,711.8
Earnings before income taxes	99.0	84.3	260.1	230.3
Operating Segments \| Engine Products segment
Segment Reporting Information [Line Items]
Net sales	472.3	405.6	1,356.8	1,121.4
Earnings before income taxes	67.8	63.1	185.9	157.2
Operating Segments \| Industrial Products segment
Segment Reporting Information [Line Items]
Net sales	227.7	202.6	652.7	590.4
Earnings before income taxes	34.8	31.9	97.0	94.5
Corporate, Non-Segment \| Corporate and Unallocated
Segment Reporting Information [Line Items]
Earnings before income taxes	$ (3.6)	$ (10.7)	$ (22.8)	$ (21.4)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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