COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	3 Months Ended
Dec. 31, 2024 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 187,800
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	301,045
2026	293,276
2027	195,638
2028	158,332
2029	138,426
Thereafter	1,006,805
ES
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	92,960
2026	55,311
2027	35,103
2028	24,993
2029	13,717
Thereafter	51,754
ES \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	40,459
2026	1,272
2027	0
2028	0
2029	0
Thereafter	0
ES \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	12,443
2026	11,967
2027	5,452
2028	3,500
2029	2,712
Thereafter	4,068
ES \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	40,058
2026	42,072
2027	29,651
2028	21,493
2029	11,005
Thereafter	47,686
Annual pipeline obligation to be paid over 10 year period	4,000
NJNG
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	208,085
2026	237,965
2027	160,535
2028	133,339
2029	124,709
Thereafter	955,051
NJNG \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	20,303
2026	0
2027	0
2028	0
2029	0
Thereafter	0
NJNG \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	26,747
2026	22,669
2027	11,207
2028	4,900
2029	0
Thereafter	0
NJNG \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2025	161,035
2026	215,296
2027	149,328
2028	128,439
2029	124,709
Thereafter	$ 955,051
Minimum \| ES
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	1 year
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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Purchase Obligation, To Be Paid, After Year Four

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

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Storage and Pipeline Capacity, Term of Contract

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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 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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Amount of recorded unconditional purchase obligation to be paid in remainder of current fiscal year.

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