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DERIVATIVES AND RISK MANAGEMENT (Commodity Contract Commitments) (Details)	3 Months Ended
	Nov. 30, 2016 t
Aluminum | Long
Derivative [Line Items]
Commodity contract commitments	1,822
Copper | Long
Derivative [Line Items]
Commodity contract commitments	237
Copper | Short
Derivative [Line Items]
Commodity contract commitments	5,160
Zinc | Long
Derivative [Line Items]
Commodity contract commitments	22

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Nominal mass used to calculate payments on a derivative instrument.

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