COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	9 Months Ended
Jun. 30, 2022 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 198,000
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	179,050
2023	346,746
2024	184,632
2025	187,384
2026	168,196
Thereafter	1,231,263
Energy Services
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	93,055
2023	145,386
2024	54,965
2025	33,487
2026	30,217
Thereafter	35,114
Energy Services \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	68,598
2023	69,392
2024	557
2025	0
2026	0
Thereafter	0
Energy Services \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	6,054
2023	20,671
2024	12,606
2025	6,450
2026	3,797
Thereafter	3,027
Energy Services \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	18,403
2023	55,323
2024	41,802
2025	27,037
2026	26,420
Thereafter	32,087
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	85,995
2023	201,360
2024	129,667
2025	153,897
2026	137,979
Thereafter	1,196,149
Natural Gas Distribution \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	37,381
2023	4,770
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	12,585
2023	47,476
2024	35,322
2025	17,362
2026	10,266
Thereafter	14,320
Natural Gas Distribution \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2022	36,029
2023	149,114
2024	94,345
2025	136,535
2026	127,713
Thereafter	$ 1,181,829
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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