Goodwill And Other Intangible Assets (Reconciliation Of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Apr. 30, 2015
Goodwill [Line Items]
Beginning Balance	$ 166,406us-gaap_Goodwill
Goodwill acquired	60,266us-gaap_GoodwillAcquiredDuringPeriod
Foreign exchange translation	(8,417)us-gaap_GoodwillTranslationAdjustments
Ending Balance	218,255us-gaap_Goodwill
Engine Products [Member]
Goodwill [Line Items]
Beginning Balance	72,373
Foreign exchange translation	(1,263)
Ending Balance	71,110
Industrial Products [Member]
Goodwill [Line Items]
Beginning Balance	94,033
Goodwill acquired	60,266
Foreign exchange translation	(7,154)
Ending Balance	$ 147,145

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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