GOODWILL AND OTHER INTANGIBLE ASSETS (Changes in the Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Feb. 28, 2018	Feb. 28, 2018
Goodwill [Roll Forward]
Goodwill, gross, balance, beginning		$ 77,310
Acquisitions		0
Foreign currency translation		110
Impairment		(514)
Reclassification to assets of discontinued operations		(1,982)
Goodwill, gross, balance, ending	$ 74,924	74,924
Accumulated impairment losses, beginning		(12,395)
Foreign currency translation		(7)
Reclassification to assets of discontinued operations		1,982
Accumulated impairment losses, ending	(10,420)	(10,420)
Balance at August 31, 2017		64,915
Acquisitions		0
Foreign currency translation		103
Impairment		(514)
Balance at February 28, 2018	64,504	64,504
Americas Recycling
Goodwill [Roll Forward]
Goodwill, gross, balance, beginning		9,751
Acquisitions		0
Foreign currency translation		0
Impairment		0
Reclassification to assets of discontinued operations		0
Goodwill, gross, balance, ending	9,751	9,751
Accumulated impairment losses, beginning		(9,751)
Foreign currency translation		0
Reclassification to assets of discontinued operations		0
Accumulated impairment losses, ending	(9,751)	(9,751)
Balance at August 31, 2017		0
Acquisitions		0
Foreign currency translation		0
Impairment		0
Balance at February 28, 2018	0	0
Americas Mills
Goodwill [Roll Forward]
Goodwill, gross, balance, beginning		4,970
Acquisitions		0
Foreign currency translation		0
Impairment		0
Reclassification to assets of discontinued operations		0
Goodwill, gross, balance, ending	4,970	4,970
Accumulated impairment losses, beginning		0
Foreign currency translation		0
Reclassification to assets of discontinued operations		0
Accumulated impairment losses, ending	0	0
Balance at August 31, 2017		4,970
Acquisitions		0
Foreign currency translation		0
Impairment		0
Balance at February 28, 2018	4,970	4,970
Americas Fabrication
Goodwill [Roll Forward]
Goodwill, gross, balance, beginning		57,943
Acquisitions		0
Foreign currency translation		0
Impairment		(514)
Reclassification to assets of discontinued operations		0
Goodwill, gross, balance, ending	57,429	57,429
Accumulated impairment losses, beginning		(493)
Foreign currency translation		0
Reclassification to assets of discontinued operations		0
Accumulated impairment losses, ending	(493)	(493)
Balance at August 31, 2017		57,450
Acquisitions		0
Foreign currency translation		0
Impairment	(500)	(514)
Balance at February 28, 2018	56,936	56,936
International Mill
Goodwill [Roll Forward]
Goodwill, gross, balance, beginning		2,664
Acquisitions		0
Foreign currency translation		110
Impairment		0
Reclassification to assets of discontinued operations		0
Goodwill, gross, balance, ending	2,774	2,774
Accumulated impairment losses, beginning		(169)
Foreign currency translation		(7)
Reclassification to assets of discontinued operations		0
Accumulated impairment losses, ending	(176)	(176)
Balance at August 31, 2017		2,495
Acquisitions		0
Foreign currency translation		103
Impairment		0
Balance at February 28, 2018	2,598	2,598
International Marketing and Distribution
Goodwill [Roll Forward]
Goodwill, gross, balance, beginning		1,982
Acquisitions		0
Foreign currency translation		0
Impairment		0
Reclassification to assets of discontinued operations		(1,982)
Goodwill, gross, balance, ending	0	0
Accumulated impairment losses, beginning		(1,982)
Foreign currency translation		0
Reclassification to assets of discontinued operations		1,982
Accumulated impairment losses, ending	0	0
Balance at August 31, 2017		0
Acquisitions		0
Foreign currency translation		0
Impairment		0
Balance at February 28, 2018	$ 0	$ 0