Segment Reporting (Summary Of Segment Detail) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014	Jul. 31, 2014
Segment Reporting Information [Line Items]
Net sales	$ 568,013us-gaap_SalesRevenueGoodsNet	$ 624,234us-gaap_SalesRevenueGoodsNet	$ 1,761,467us-gaap_SalesRevenueGoodsNet	$ 1,805,240us-gaap_SalesRevenueGoodsNet
Earnings before income taxes	65,722	94,182	210,816	259,851
Assets	1,845,832us-gaap_Assets	1,898,001us-gaap_Assets	1,845,832us-gaap_Assets	1,898,001us-gaap_Assets	1,942,411us-gaap_Assets
Engine Products [Member]
Segment Reporting Information [Line Items]
Net sales	368,046	402,157	1,115,875	1,160,948
Earnings before income taxes	47,760	61,432	142,356	170,799
Assets	886,407	890,639	886,407	890,639
Industrial Products [Member]
Segment Reporting Information [Line Items]
Net sales	199,967	222,077	645,592	644,292
Earnings before income taxes	23,183	32,507	88,272	91,682
Assets	632,296	552,533	632,296	552,533
Corporate & Unallocated [Member]
Segment Reporting Information [Line Items]
Earnings before income taxes	(5,221)	243	(19,812)	(2,630)
Assets	$ 327,129	$ 454,829	$ 327,129	$ 454,829

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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

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