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DERIVATIVES AND RISK MANAGEMENT - Commodity Contract Commitments (Details)	12 Months Ended
	Aug. 31, 2019 t
Aluminum | Long
Derivative [Line Items]
Commodity contract commitments	2,125
Copper | Long
Derivative [Line Items]
Commodity contract commitments	510
Copper | Short
Derivative [Line Items]
Commodity contract commitments	6,158

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Nominal mass used to calculate payments on a derivative instrument.

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