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DERIVATIVES AND RISK MANAGEMENT (Commodity Contract Commitments) (Details)	3 Months Ended
	Nov. 30, 2017 t
Aluminum | Long
Derivative [Line Items]
Commodity contract commitments	3,475
Aluminum | Short
Derivative [Line Items]
Commodity contract commitments	900
Copper | Long
Derivative [Line Items]
Commodity contract commitments	714
Copper | Short
Derivative [Line Items]
Commodity contract commitments	6,214

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