COMMITMENTS AND CONTINGENT LIABILITIES - LEGAL PROCEEDINGS (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2024	Sep. 30, 2024
Site Contingency [Line Items]
Manufactured gas plant remediation	$ 161,024	$ 161,650
Recovery from third party of environmental remediation cost, period	7 years
Regulatory assets	$ 612,595	$ 609,192
Expended, net of recoveries
Site Contingency [Line Items]
Regulatory assets	74,100
Minimum
Site Contingency [Line Items]
Product liability contingency, loss exposure in excess of accrual, best estimate	130,900
Maximum
Site Contingency [Line Items]
Product liability contingency, loss exposure in excess of accrual, best estimate	$ 194,600

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