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v3.20.1

DERIVATIVES (Commodity Contract Commitments) (Details) MWh in Millions | 6 Months Ended
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Feb. 29, 2020 MWh t
Aluminum | Long |
Derivative [Line Items] |
Commodity contract commitments | 2,100
Copper | Long |
Derivative [Line Items] |
Commodity contract commitments | 318
Copper | Short |
Derivative [Line Items] |
Commodity contract commitments | 5,454
Electricity | Long |
Derivative [Line Items] |
Commodity contract commitment, electricity | MWh | 2

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