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- Definition

Site Contingency, Recovery from Third Party of Environmental Remediation Cost, Period

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

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- Definition

Best estimate of the reasonably possible loss exposure in excess of the amount accrued for damages pertaining to a specified product.

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-Name Accounting Standards Codification
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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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COMMITMENTS AND CONTINGENT LIABILITIES - LEGAL PROCEEDINGS (Details) - USD ($) $ in Thousands			6 Months Ended
	Mar. 16, 2020	Mar. 15, 2020	Mar. 31, 2020	Sep. 30, 2019
Site Contingency [Line Items]
Manufactured gas plant remediation			$ 128,868	$ 131,080
Recovery from third party of environmental remediation cost, period			7 years
Regulatory assets			$ 450,039	496,637
Expended, net of recoveries
Site Contingency [Line Items]
Regulatory assets			35,856	$ 38,351
RAC
Site Contingency [Line Items]
Approved rate, amount	$ 9,700	$ 8,500
Minimum
Site Contingency [Line Items]
Product liability contingency, loss exposure in excess of accrual, best estimate			115,900
Maximum
Site Contingency [Line Items]
Product liability contingency, loss exposure in excess of accrual, best estimate			$ 186,200