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DERIVATIVES AND RISK MANAGEMENT (Commodity Contract Commitments) (Details)	6 Months Ended
	Feb. 28, 2017 t
Aluminum | Long
Derivative [Line Items]
Commodity contract commitments	2,630
Aluminum | Short
Derivative [Line Items]
Commodity contract commitments	325
Copper | Long
Derivative [Line Items]
Commodity contract commitments	419
Copper | Short
Derivative [Line Items]
Commodity contract commitments	4,808
Zinc | Long
Derivative [Line Items]
Commodity contract commitments	15

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