Segment Reporting (Summary Of Segment Detail) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2016	Apr. 30, 2015
Segment Reporting Information [Line Items]
Net sales	$ 571.3	$ 575.6	$ 1,626.5	$ 1,760.6
Earnings Before Income Taxes	72.1	67.8	174.9	210.5
Operating Segments \| Engine Product segment
Segment Reporting Information [Line Items]
Net sales	357.3	368.0	1,024.8	1,115.8
Earnings Before Income Taxes	48.7	47.7	112.1	142.3
Operating Segments \| Industrial Product segment
Segment Reporting Information [Line Items]
Net sales	214.0	207.6	601.7	644.8
Earnings Before Income Taxes	29.9	25.3	81.6	88.0
Corporate, Non-Segment \| Corporate and Unallocated
Segment Reporting Information [Line Items]
Earnings Before Income Taxes	$ (6.5)	$ (5.2)	$ (18.8)	$ (19.8)

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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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ 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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