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DERIVATIVE INSTRUMENTS - VOLUME (Details) - Bcf | 6 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Sep. 30, 2023
NJNG | Long | Futures |  |
Derivative [Line Items] |  |
Notional amount | 23.8 | 32.1
NJNG | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | 5.0 | 12.1
ES | Long | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount |  | 0.2
ES | Short | Futures |  |
Derivative [Line Items] |  |
Notional amount | (3.8) | (6.9)
ES | Short | Physical Commodity |  |
Derivative [Line Items] |  |
Notional amount | (3.2) |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-5 + Details
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