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DERIVATIVE INSTRUMENTS - VOLUME (Details) - Bcf | Jun. 30, 2021 | Sep. 30, 2020
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Natural Gas Distribution | Long | Futures |  |
Derivative [Line Items] |  |
Notional amount | 18.1 | 23.7
Natural Gas Distribution | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | 9.4 | 6.0
Energy Services | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | 3.5 | 5.0
Energy Services | Short | Futures |  |
Derivative [Line Items] |  |
Notional amount | 22.1 | 27.5
Energy Services | Short | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 0.5 | 1.8

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