GOODWILL AND OTHER INTANGIBLE ASSETS (Narrative) (Details) - USD ($)	12 Months Ended
Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2014
Goodwill	$ 66,373,000	$ 66,383,000	$ 74,319,000
Goodwill impairment charges	0	7,267,000	0
Amortization expense for intangible assets	$ 3,600,000	6,900,000	5,100,000
Intangible assets excluding favorable land leases
Weighted average remaining useful lives	10 years
Favorable land leases
Weighted average remaining useful lives	48 years
One reporting unit within Americas Fabrication
Goodwill	$ 51,300,000	51,300,000
Reporting unit, percentage of fair value in excess of carrying amount (percent)	20.00%
Americas Recycling
Goodwill	$ 0	0	$ 7,267,000
Goodwill impairment charges	$ 0	$ 7,267,000

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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