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DERIVATIVE INSTRUMENTS - VOLUME (Details) - Bcf | Jun. 30, 2020 | Sep. 30, 2019
--- | --- | ---
Natural Gas Distribution | Long | Futures |  |
Derivative [Line Items] |  |
Notional amount | 18.8 | 27.6
Natural Gas Distribution | Long | Physical |  |
Derivative [Line Items] |  |
Notional amount | 10.3 | 11.6
Energy Services | Long | Physical |  |
Derivative [Line Items] |  |
Notional amount | 12.6 | 44.5
Energy Services | Short | Futures |  |
Derivative [Line Items] |  |
Notional amount | (38.4) | (29.6)
Energy Services | Short | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 2.3 | 5.0

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