Segment Reporting (Summary Of Segment Detail) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2016	Jan. 31, 2015
Segment Reporting Information [Line Items]
Net sales	$ 517.2	$ 588.5	$ 1,055.2	$ 1,185.0
Earnings Before Income Taxes	49.4	65.4	102.8	142.7
Operating Segments \| Engine Product segment
Segment Reporting Information [Line Items]
Net sales	320.9	357.1	667.5	747.8
Earnings Before Income Taxes	27.4	41.5	63.4	94.6
Operating Segments \| Industrial Product segment
Segment Reporting Information [Line Items]
Net sales	196.3	231.4	387.7	437.2
Earnings Before Income Taxes	27.7	35.1	51.7	62.7
Corporate, Non-Segment \| Corporate and Unallocated
Segment Reporting Information [Line Items]
Earnings Before Income Taxes	$ (5.7)	$ (11.2)	$ (12.3)	$ (14.6)

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Article 5

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