COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	3 Months Ended
Dec. 31, 2021 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 191,000
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	312,523
2023	243,740
2024	179,876
2025	164,345
2026	145,545
Thereafter	1,142,767
Energy Services
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	165,993
2023	60,662
2024	28,957
2025	24,149
2026	17,586
Thereafter	19,554
Energy Services \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	101,257
2023	1,857
2024	0
2025	0
2026	0
Thereafter	0
Energy Services \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	15,217
2023	12,177
2024	6,698
2025	5,018
2026	2,375
Thereafter	906
Energy Services \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	49,519
2023	46,628
2024	22,259
2025	19,131
2026	15,211
Thereafter	18,648
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
2022	146,530
2023	183,078
2024	150,919
2025	140,196
2026	127,959
Thereafter	1,123,213
Natural Gas Distribution \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	7,668
2023	0
2024	0
2025	0
2026	0
Thereafter	0
Natural Gas Distribution \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	34,738
2023	38,107
2024	17,743
2025	7,740
2026	2,171
Thereafter	1,879
Natural Gas Distribution \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	104,124
2023	144,971
2024	133,176
2025	132,456
2026	125,788
Thereafter	$ 1,121,334
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 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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