Goodwill and Other Intangible Assets (Carrying Amount in Goodwill by Segments) (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 64,387	$ 64,671
Acquisition of Net Irrigate	3,265
Foreign currency translation	352	(284)
Goodwill, Ending Balance	68,004	64,387
Irrigation [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	48,567	48,591
Acquisition of Net Irrigate	3,265
Foreign currency translation	(30)	(24)
Goodwill, Ending Balance	51,802	48,567
Infrastructure [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	15,820	16,080
Foreign currency translation	382	(260)
Goodwill, Ending Balance	$ 16,202	$ 15,820

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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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

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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.

+ References

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