DERIVATIVE INSTRUMENTS - OFFSETTING OF ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Sep. 30, 2024
ES
Asset Derivatives
Fair Value	$ 13,260	$ 7,598
Amounts Offset	(6,598)	(2,611)
Collateral Received/Pledged	0	(1,170)
Net Value	6,662	3,817
Liability Derivatives
Fair Value	12,757	17,180
Amounts Offset	(6,598)	(2,611)
Collateral Received/Pledged	(4,152)	(5,551)
Net Value	2,007	9,018
ES \| Physical commodity contracts
Asset Derivatives
Fair Value	6,731	2,387
Amounts Offset	(3,898)	(535)
Collateral Received/Pledged	0	0
Net Value	2,833	1,852
Liability Derivatives
Fair Value	10,057	15,104
Amounts Offset	(3,898)	(535)
Collateral Received/Pledged	(4,152)	(5,551)
Net Value	2,007	9,018
ES \| Financial commodity contracts
Asset Derivatives
Fair Value	6,529	5,211
Amounts Offset	(2,700)	(2,076)
Collateral Received/Pledged	0	(1,170)
Net Value	3,829	1,965
Liability Derivatives
Fair Value	2,700	2,076
Amounts Offset	(2,700)	(2,076)
Collateral Received/Pledged	0	0
Net Value	0	0
NJNG
Asset Derivatives
Fair Value	271	21
Amounts Offset	(16)	(13)
Collateral Received/Pledged	(137)	0
Net Value	118	8
Liability Derivatives
Fair Value	23	581
Amounts Offset	(16)	(13)
Collateral Received/Pledged	0	(2)
Net Value	7	566
NJNG \| Physical commodity contracts
Asset Derivatives
Fair Value	118	21
Amounts Offset	0	(13)
Collateral Received/Pledged	0	0
Net Value	118	8
Liability Derivatives
Fair Value	7	579
Amounts Offset	0	(13)
Collateral Received/Pledged	0	0
Net Value	7	566
NJNG \| Financial commodity contracts
Asset Derivatives
Fair Value	153	0
Amounts Offset	(16)	0
Collateral Received/Pledged	(137)	0
Net Value	0	0
Liability Derivatives
Fair Value	16	2
Amounts Offset	(16)	0
Collateral Received/Pledged	0	(2)
Net Value	$ 0	$ 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.

+ References

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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, before effects of master netting arrangements, of a 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. Includes liabilities elected not to be offset. Excludes liabilities 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 liability or 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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