COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	12 Months Ended
Sep. 30, 2024 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 252,800
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	383,061
2025	237,841
2026	188,020
2027	155,973
2028	138,215
Thereafter	1,006,789
Operating leases, future minimum payments due, next five years (not more than)	9,000
Thereafter	233,942
ES
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	106,830
2025	53,209
2026	34,995
2027	24,993
2028	13,717
Thereafter	51,754
ES \| Natural gas purchases
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	42,427
2025	1,155
2026	0
2027	0
2028	0
Thereafter	0
ES \| Storage demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	16,453
2025	11,857
2026	5,452
2027	3,500
2028	2,712
Thereafter	4,068
ES \| Pipeline demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	47,950
2025	40,197
2026	29,543
2027	21,493
2028	11,005
Thereafter	47,686
Annual pipeline obligation to be paid over 10 year period	4,000
NJNG
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	276,231
2025	184,632
2026	153,025
2027	130,980
2028	124,498
Thereafter	955,035
NJNG \| Natural gas purchases
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	23,392
2025	0
2026	0
2027	0
2028	0
Thereafter	0
NJNG \| Storage demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	38,214
2025	22,678
2026	11,207
2027	4,900
2028	0
Thereafter	0
NJNG \| Pipeline demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	214,625
2025	161,954
2026	141,818
2027	126,080
2028	124,498
Thereafter	$ 955,035
Minimum
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	1 year
Minimum \| ES
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	1 year
Maximum
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	10 years
Maximum \| ES
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	10 years

Current Charges Recoverable Through Basic Gas Supply Service as shown for the reporting period

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- Definition

Lessee, Operating Lease, Liability, Payments, Due Next Five Years

+ References

No definition available.

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- Definition

Recorded Unconditional Purchase Obligation, To Be Paid Annual By Counterparty Over 10 Year Period

+ References

No definition available.

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- Definition

Storage and Pipeline Capacity, Term of Contract

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-6

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Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- References

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