SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - PROPERTY PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022
Property Classifications
Total property, plant and equipment	$ 5,990,539	$ 5,515,716
Accumulated depreciation and amortization	(968,484)	(865,790)
Property, plant and equipment, net	5,022,055	4,649,926
Distribution facilities
Property Classifications
Total property, plant and equipment	$ 3,063,111	2,797,936
Distribution facilities \| Minimum
Property Classifications
Estimated Useful Lives	11 years
Distribution facilities \| Maximum
Property Classifications
Estimated Useful Lives	54 years
Transmission facilities
Property Classifications
Total property, plant and equipment	$ 650,817	649,241
Transmission facilities \| Minimum
Property Classifications
Estimated Useful Lives	28 years
Transmission facilities \| Maximum
Property Classifications
Estimated Useful Lives	42 years
Storage facilities
Property Classifications
Total property, plant and equipment	$ 85,603	85,449
Storage facilities \| Minimum
Property Classifications
Estimated Useful Lives	27 years
Storage facilities \| Maximum
Property Classifications
Estimated Useful Lives	86 years
Solar property
Property Classifications
Total property, plant and equipment	$ 864,838	710,224
Solar property \| Minimum
Property Classifications
Estimated Useful Lives	20 years
Solar property \| Maximum
Property Classifications
Estimated Useful Lives	35 years
Storage and transportation property
Property Classifications
Total property, plant and equipment	$ 884,647	850,186
Storage and transportation property \| Minimum
Property Classifications
Estimated Useful Lives	5 years
Storage and transportation property \| Maximum
Property Classifications
Estimated Useful Lives	50 years
All other property
Property Classifications
Total property, plant and equipment	$ 61,327	60,914
All other property \| Minimum
Property Classifications
Estimated Useful Lives	5 years
All other property \| Maximum
Property Classifications
Estimated Useful Lives	40 years
Construction work in progress
Property Classifications
Total property, plant and equipment	$ 380,196	$ 361,766

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Public Utilities And Other Property, Plant and Equipment, Net

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(14))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482099/360-10-50-1

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8))
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-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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-Section S99
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-Section 50
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-URI https://asc.fasb.org//1943274/2147482099/360-10-50-1

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