Goodwill And Other Intangible Assets (Carrying Amount In Goodwill By Segments) (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 77,131	$ 76,803
Divestiture of businesses	(12,294)
Foreign currency translation	(167)	328
Goodwill, Ending Balance	64,671	77,131
Irrigation [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	60,978	60,942
Divestiture of businesses	(12,294)
Foreign currency translation	(93)	36
Goodwill, Ending Balance	48,591	60,978
Infrastructure [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	16,153	15,861
Foreign currency translation	(73)	292
Goodwill, Ending Balance	$ 16,080	$ 16,153

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
-Subparagraph (a)
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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