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DERIVATIVES (Commodity Contract Commitments) (Details) MWh in Millions | 3 Months Ended
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Nov. 30, 2019 MWh t
Aluminum | Long |
Derivative [Line Items] |
Commodity contract commitments | 1,975
Copper | Long |
Derivative [Line Items] |
Commodity contract commitments | 987
Copper | Short |
Derivative [Line Items] |
Commodity contract commitments | 7,178
Electricity | Long |
Derivative [Line Items] |
Commodity contract commitment, electricity | MWh | 2

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