GOODWILL AND OTHER INTANGIBLE ASSETS (Changes in the Carrying Amount of Goodwill) (Details) $ in Thousands	6 Months Ended
	Feb. 28, 2017 USD ($)
Goodwill [Roll Forward]
Balance at August 31, 2016	$ 76,772
Acquisitions	306
Foreign currency translation	(156)
Balance at February 28, 2017	76,922
Foreign currency translation	(10,399)
Foreign currency translation	7
Accumulated impairment losses	(10,392)
Balance at August 31, 2016	66,373
Acquisitions	306
Foreign currency translation	(149)
Balance at February 28, 2017	66,530
Americas Recycling
Goodwill [Roll Forward]
Balance at August 31, 2016	9,751
Acquisitions	0
Foreign currency translation	0
Balance at February 28, 2017	9,751
Foreign currency translation	(9,751)
Foreign currency translation	0
Accumulated impairment losses	(9,751)
Balance at August 31, 2016	0
Acquisitions	0
Foreign currency translation	0
Balance at February 28, 2017	0
Americas Mills
Goodwill [Roll Forward]
Balance at August 31, 2016	4,970
Acquisitions	0
Foreign currency translation	0
Balance at February 28, 2017	4,970
Foreign currency translation	0
Foreign currency translation	0
Accumulated impairment losses	0
Balance at August 31, 2016	4,970
Acquisitions	0
Foreign currency translation	0
Balance at February 28, 2017	4,970
Americas Fabrication
Goodwill [Roll Forward]
Balance at August 31, 2016	57,637
Acquisitions	306
Foreign currency translation	0
Balance at February 28, 2017	57,943
Foreign currency translation	(493)
Foreign currency translation	0
Accumulated impairment losses	(493)
Balance at August 31, 2016	57,144
Acquisitions	306
Foreign currency translation	0
Balance at February 28, 2017	57,450
International Mill
Goodwill [Roll Forward]
Balance at August 31, 2016	2,432
Acquisitions	0
Foreign currency translation	(98)
Balance at February 28, 2017	2,334
Foreign currency translation	(155)
Foreign currency translation	7
Accumulated impairment losses	(148)
Balance at August 31, 2016	2,277
Acquisitions	0
Foreign currency translation	(91)
Balance at February 28, 2017	2,186
International Marketing and Distribution
Goodwill [Roll Forward]
Balance at August 31, 2016	1,982
Acquisitions	0
Foreign currency translation	(58)
Balance at February 28, 2017	1,924
Foreign currency translation	0
Foreign currency translation	0
Accumulated impairment losses	0
Balance at August 31, 2016	1,982
Acquisitions	0
Foreign currency translation	(58)
Balance at February 28, 2017	$ 1,924