Segment Reporting (Summary Of Segment Detail) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 550.6	$ 517.2	$ 1,103.6	$ 1,055.2
Earnings Before Income Taxes	66.3	49.4	146.0	102.8
Operating Segments \| Engine Products segment
Segment Reporting Information [Line Items]
Net sales	361.9	320.9	715.7	667.5
Earnings Before Income Taxes	48.7	27.4	94.1	63.4
Operating Segments \| Industrial Products segment
Segment Reporting Information [Line Items]
Net sales	188.7	196.3	387.9	387.7
Earnings Before Income Taxes	24.3	27.7	62.6	51.7
Corporate, Non-Segment \| Corporate and Unallocated
Segment Reporting Information [Line Items]
Earnings Before Income Taxes	$ (6.7)	$ (5.7)	$ (10.7)	$ (12.3)

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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