GOODWILL AND OTHER INTANGIBLE ASSETS (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Goodwill	$ 64,138	$ 64,310	$ 64,915
Goodwill impairment		1,982
Amortization expense for intangible assets	$ 2,200	2,200	2,100
Favorable land leases
Weighted average remaining useful lives	85 years
One reporting unit within Americas Fabrication
Goodwill	$ 51,100	51,100
Reporting unit, percentage of fair value in excess of carrying amount (percent)	29.30%
International Marketing and Distribution
Goodwill	$ 0	0	0
Goodwill impairment		1,982
Americas Recycling
Goodwill	$ 0	0	$ 0
Goodwill impairment		$ 0
Minimum
Weighted average remaining useful lives	3 years
Maximum
Weighted average remaining useful lives	15 years

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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