GOODWILL AND OTHER INTANGIBLE ASSETS (Changes in the Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands	9 Months Ended
May 31, 2016	Aug. 31, 2015
Goodwill [Line Items]
Goodwill	$ 76,730	$ 76,787
Accumulated impairment losses	(10,397)	(10,404)
Goodwill, net	66,333	66,383
Foreign currency translation	(50)
Americas Recycling
Goodwill [Line Items]
Goodwill	9,751	9,751
Accumulated impairment losses	(9,751)	(9,751)
Goodwill, net	0	0
Foreign currency translation	0
Americas Mills
Goodwill [Line Items]
Goodwill	4,970	4,970
Accumulated impairment losses	0	0
Goodwill, net	4,970	4,970
Foreign currency translation	0
Americas Fabrication
Goodwill [Line Items]
Goodwill	57,637	57,637
Accumulated impairment losses	(493)	(493)
Goodwill, net	57,144	57,144
Foreign currency translation	0
International Mill
Goodwill [Line Items]
Goodwill	2,412	2,517
Accumulated impairment losses	(153)	(160)
Goodwill, net	2,259	2,357
Foreign currency translation	(98)
International Marketing and Distribution
Goodwill [Line Items]
Goodwill	1,960	1,912
Accumulated impairment losses	0	0
Goodwill, net	1,960	$ 1,912
Foreign currency translation	$ 48

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=64834752&loc=SL49117168-202975

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