DERIVATIVE INSTRUMENTS - BROKER MARGIN DEPOSITS (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Sep. 30, 2024
NJNG \| Assets, Current
Derivative [Line Items]
Broker margin - current assets	$ 7,803	$ 4,975
ES \| Assets, Current
Derivative [Line Items]
Broker margin - current assets	12,087	8,268
ES \| Liabilities, Current
Derivative [Line Items]
Broker margin - current liabilities	$ 0	$ 1,146

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.

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

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Amount of other payables due to broker-dealers or clearing organizations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 940
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481833/940-20-45-3

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Amount of other receivables due from broker-dealers or clearing organizations.

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