Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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GOODWILL AND OTHER INTANGIBLE ASSETS (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017	Aug. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross carrying amounts of the intangible assets subject to amortization	$ 21,500		$ 21,500		$ 19,700
Amortization expense for intangible assets	600	$ 700	1,100	$ 900
Impairment			(514)
Americas Fabrication
Finite-Lived Intangible Assets [Line Items]
Impairment	(500)		$ (514)
MMFX Technologies Corporation \| Patents
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 7,000
Useful life of intangible assets acquired	7 years 6 months