DERIVATIVES (Commodity Contract Commitments) (Details) MWh in Millions	9 Months Ended
May 31, 2020 MWh t
Aluminum \| Long
Derivative [Line Items]
Commodity contract commitments	2,300
Aluminum \| Short
Derivative [Line Items]
Commodity contract commitments	1,100
Copper \| Long
Derivative [Line Items]
Commodity contract commitments	318
Copper \| Short
Derivative [Line Items]
Commodity contract commitments	4,990
Electricity \| Long
Derivative [Line Items]
Commodity contract commitment, electricity \| MWh	2

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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