COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	6 Months Ended
Mar. 31, 2023 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 186,400
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	172,673
2024	263,349
2025	236,524
2026	183,406
2027	162,271
Thereafter	1,098,435
Energy Services
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	65,856
2024	80,828
2025	54,507
2026	38,606
2027	28,519
Thereafter	35,504
Energy Services \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	24,692
2024	13,502
2025	1,721
2026	0
2027	0
Thereafter	0
Energy Services \| Storage demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	10,825
2024	16,688
2025	7,838
2026	4,654
2027	2,166
Thereafter	794
Energy Services \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	30,339
2024	50,638
2025	44,948
2026	33,952
2027	26,353
Thereafter	34,710
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	106,817
2024	182,521
2025	182,017
2026	144,800
2027	133,752
Thereafter	1,062,931
Natural Gas Distribution \| Natural gas purchases
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	14,833
2024	539
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	22,472
2024	42,049
2025	30,048
2026	14,353
2027	9,541
Thereafter	4,772
Natural Gas Distribution \| Pipeline demand fees
Natural Gas Purchases and Future Demand Fees, Next Five Fiscal Years
2023	69,512
2024	139,933
2025	151,969
2026	130,447
2027	124,211
Thereafter	$ 1,058,159
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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