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DERIVATIVES (Commodity Contract Commitments) (Details) MWh in Thousands	9 Months Ended
	May 31, 2021 MWh t
Aluminum | Long
Derivative [Line Items]
Commodity contract commitments	4,150
Aluminum | Short
Derivative [Line Items]
Commodity contract commitments	1,750
Copper | Long
Derivative [Line Items]
Commodity contract commitments	624
Copper | Short
Derivative [Line Items]
Commodity contract commitments	8,981
Electricity | Long
Derivative [Line Items]
Commodity contract commitment, electricity | MWh	1,917

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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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- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

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- Definition

Nominal mass used to calculate payments on a derivative instrument.

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