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DERIVATIVE INSTRUMENTS - VOLUME (Details) - Bcf | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2021 | Sep. 30, 2021
Natural Gas Distribution | Long | Futures |  |
Derivative [Line Items] |  |
Notional amount | 24.0 | 22.2
Natural Gas Distribution | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | 1.5 | 7.6
Energy Services | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | (4.9) | 0.6
Energy Services | Short | Futures |  |
Derivative [Line Items] |  |
Notional amount | (22.0) | (13.4)
Energy Services | Short | Swaps |  |
Derivative [Line Items] |  |
Notional amount | (0.2) | (0.3)

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