COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	3 Months Ended
Dec. 31, 2023 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 208,100
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	258,471
2025	287,512
2026	196,466
2027	168,667
2028	136,473
Thereafter	988,375
ES
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	90,653
2025	63,439
2026	43,229
2027	29,861
2028	17,399
Thereafter	21,428
ES \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	41,616
2025	1,826
2026	0
2027	0
2028	0
Thereafter	0
ES \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	13,788
2025	15,297
2026	11,467
2027	5,478
2028	3,505
Thereafter	6,780
ES \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	35,249
2025	46,316
2026	31,762
2027	24,383
2028	13,894
Thereafter	14,648
Annual pipeline obligation to be paid over 10 year period	4,000
NJNG
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	167,818
2025	224,073
2026	153,237
2027	138,806
2028	119,074
Thereafter	966,947
NJNG \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	20,156
2025	0
2026	0
2027	0
2028	0
Thereafter	0
NJNG \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	31,211
2025	30,645
2026	14,971
2027	10,163
2028	5,084
Thereafter	0
NJNG \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2024	116,451
2025	193,428
2026	138,266
2027	128,643
2028	113,990
Thereafter	$ 966,947
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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