DERIVATIVE INSTRUMENTS - OFFSETTING OF ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024
ES
Asset Derivatives
Fair Value	$ 6,776	$ 7,598
Amounts Offset	(3,539)	(2,611)
Collateral Received/Pledged	0	(1,170)
Net Value	3,237	3,817
Liability Derivatives
Fair Value	22,729	17,180
Amounts Offset	(3,539)	(2,611)
Collateral Received/Pledged	(6,576)	(5,551)
Net Value	12,614	9,018
ES \| Physical commodity contracts
Asset Derivatives
Fair Value	3,681	2,387
Amounts Offset	(444)	(535)
Collateral Received/Pledged	0	0
Net Value	3,237	1,852
Liability Derivatives
Fair Value	19,101	15,104
Amounts Offset	(444)	(535)
Collateral Received/Pledged	(6,043)	(5,551)
Net Value	12,614	9,018
ES \| Financial commodity contracts
Asset Derivatives
Fair Value	3,095	5,211
Amounts Offset	(3,095)	(2,076)
Collateral Received/Pledged	0	(1,170)
Net Value	0	1,965
Liability Derivatives
Fair Value	3,628	2,076
Amounts Offset	(3,095)	(2,076)
Collateral Received/Pledged	(533)	0
Net Value	0	0
NJNG
Asset Derivatives
Fair Value	169	21
Amounts Offset	(10)	(13)
Collateral Received/Pledged	0	0
Net Value	159	8
Liability Derivatives
Fair Value	3,055	581
Amounts Offset	(10)	(13)
Collateral Received/Pledged	0	(2)
Net Value	3,045	566
NJNG \| Physical commodity contracts
Asset Derivatives
Fair Value	159	21
Amounts Offset	0	(13)
Collateral Received/Pledged	0	0
Net Value	159	8
Liability Derivatives
Fair Value	728	579
Amounts Offset	0	(13)
Collateral Received/Pledged	0	0
Net Value	728	566
NJNG \| Financial commodity contracts
Asset Derivatives
Fair Value	10	0
Amounts Offset	(10)	0
Collateral Received/Pledged	0	0
Net Value	0	0
Liability Derivatives
Fair Value	2,327	2
Amounts Offset	(10)	0
Collateral Received/Pledged	0	(2)
Net Value	$ 2,317	$ 0

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- Definition

Collateral or equivalent pledged or received against derivative liabilities.

+ References

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- Definition

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after effect of master netting arrangement and deduction of obligation to return financial collateral not offset and financial instrument subject to master netting arrangement not offset, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Includes derivative not subject to master netting arrangement or similar agreement.

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Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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