DERIVATIVES (Commodity Contract Commitments) (Details) MWh in Millions	3 Months Ended
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

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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