COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	12 Months Ended
Sep. 30, 2023 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 198,300
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	349,520
2025	240,100
2026	187,289
2027	167,926
2028	136,306
Thereafter	988,200
Operating leases, future minimum payments due, next five years (not more than)	7,900
Thereafter	213,927
ES
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	127,224
2025	53,868
2026	37,759
2027	29,112
2028	17,224
Thereafter	21,237
ES \| Natural gas purchases
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	66,525
2025	2,498
2026	0
2027	0
2028	0
Thereafter	0
ES \| Storage demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	16,944
2025	8,099
2026	6,010
2027	4,878
2028	3,505
Thereafter	6,780
ES \| Pipeline demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	43,755
2025	43,271
2026	31,749
2027	24,234
2028	13,719
Thereafter	14,457
Annual pipeline obligation to be paid over 10 year period	4,000
NJNG
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	222,296
2025	186,232
2026	149,530
2027	138,814
2028	119,082
Thereafter	966,963
NJNG \| Natural gas purchases
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	23,952
2025	0
2026	0
2027	0
2028	0
Thereafter	0
NJNG \| Storage demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	42,469
2025	30,673
2026	14,975
2027	10,163
2028	5,084
Thereafter	0
NJNG \| Pipeline demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2024	155,875
2025	155,559
2026	134,555
2027	128,651
2028	113,998
Thereafter	$ 966,963
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

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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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