COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands	12 Months Ended
Sep. 30, 2022 USD ($)
Long-term Purchase Commitment [Line Items]
Current charges recoverable through BGSS	$ 196,600
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	504,860
2023	215,578
2024	195,054
2025	173,663
2026	158,978
Thereafter	1,084,260
Operating leases, future minimum payments due, next five years (not more than)	8,000
Thereafter	190,972
Energy Services
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	277,546
2023	59,428
2024	38,735
2025	35,673
2026	25,269
Thereafter	21,543
Energy Services \| Natural gas purchases
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	199,629
2023	2,355
2024	0
2025	0
2026	0
Thereafter	0
Energy Services \| Storage demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	21,160
2023	12,607
2024	6,450
2025	3,797
2026	2,208
Thereafter	819
Energy Services \| Pipeline demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	56,757
2023	44,466
2024	32,285
2025	31,876
2026	23,061
Thereafter	20,724
Annual pipeline obligation to be paid over 10 year period	4,000
Natural Gas Distribution
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	227,314
2023	156,150
2024	156,319
2025	137,990
2026	133,709
Thereafter	1,062,717
Natural Gas Distribution \| Natural gas purchases
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	30,730
2023	0
2024	0
2025	0
2026	0
Thereafter	0
Natural Gas Distribution \| Storage demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	47,513
2023	35,345
2024	17,370
2025	10,268
2026	9,546
Thereafter	4,775
Natural Gas Distribution \| Pipeline demand fees
Purchase Obligation, Fiscal Year Maturity [Abstract]
2022	149,071
2023	120,805
2024	138,949
2025	127,722
2026	124,163
Thereafter	$ 1,057,942
Minimum
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	1 year
Minimum \| Energy Services
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	1 year
Maximum
Long-term Purchase Commitment [Line Items]
Storage and pipeline capacity, contract term	10 years
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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- Definition

Lessee, Operating Lease, Liability, Payments, Due Next Five Years

+ References

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- Definition

Recorded Unconditional Purchase Obligation, To Be Paid Annual By Counterparty Over 10 Year Period

+ References

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- Definition

Storage and Pipeline Capacity, Term of Contract

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918701-209980

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Amount of purchase arrangement to be paid after fifth 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 fifth 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 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 next 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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