COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	3 Months Ended
Dec. 31, 2022 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 191,400
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	300,487
2024	235,465
2025	198,440
2026	174,722
2027	158,995
Thereafter	1,084,244
Energy Services
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	148,378
2024	59,557
2025	40,658
2026	36,994
2027	25,294
Thereafter	21,535
Energy Services \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	91,458
2024	1,888
2025	0
2026	0
2027	0
Thereafter	0
Energy Services \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	15,844
2024	14,434
2025	8,278
2026	4,714
2027	2,207
Thereafter	818
Energy Services \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	41,076
2024	43,235
2025	32,380
2026	32,280
2027	23,087
Thereafter	20,717
Annual pipeline obligation to be paid over 10 year period	4,000
Natural Gas Distribution
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	152,109
2024	175,908
2025	157,782
2026	137,728
2027	133,701
Thereafter	1,062,709
Natural Gas Distribution \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	9,152
2024	0
2025	0
2026	0
2027	0
Thereafter	0
Natural Gas Distribution \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	32,951
2024	33,815
2025	16,848
2026	10,164
2027	9,541
Thereafter	4,772
Natural Gas Distribution \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	110,006
2024	142,093
2025	140,934
2026	127,564
2027	124,160
Thereafter	$ 1,057,937
Minimum \| Energy Services
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	1 year
Maximum \| Energy Services
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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