SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - PROPERTY PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023
Property Classifications
Total property, plant and equipment	$ 6,496,515	$ 5,990,539
Accumulated depreciation and amortization	(1,093,292)	(968,484)
Property, plant and equipment, net	5,403,223	5,022,055
Distribution facilities
Property Classifications
Total property, plant and equipment	$ 3,436,308	3,063,111
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	$ 656,098	650,817
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	$ 86,329	85,603
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	$ 885,518	864,838
Solar property \| Minimum
Property Classifications
Estimated Useful Lives	15 years
Solar property \| Maximum
Property Classifications
Estimated Useful Lives	35 years
Storage and transportation property
Property Classifications
Total property, plant and equipment	$ 929,850	884,647
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	$ 62,248	61,327
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	$ 440,164	$ 380,196

Public Utilities And Other Property, Plant and Equipment, Gross

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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/1943274/2147478777/944-210-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))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.5-02(13))
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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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

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