Public Utilities, Approved Rate, Amount

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

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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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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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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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The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

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COMMITMENTS AND CONTINGENT LIABILITIES - LEGAL PROCEEDINGS (Details) - USD ($) $ in Thousands					12 Months Ended
	Sep. 09, 2020	Sep. 08, 2020	Mar. 16, 2020	Sep. 27, 2019	Sep. 30, 2020	Sep. 30, 2019
Loss Contingencies [Line Items]
Regulatory assets					$ 527,459	$ 496,637
Regulatory liabilities-noncurrent					$ 196,450	202,435
Recovery period					7 years
Minimum
Loss Contingencies [Line Items]
Litigation settlement, gross					$ 143,100
Maximum
Loss Contingencies [Line Items]
Litigation settlement, gross					181,700
Environmental remediation costs, Liability for future expenditures
Loss Contingencies [Line Items]
Regulatory assets					150,600	$ 131,100
Environmental remediation costs, Expended, net of recoveries
Loss Contingencies [Line Items]
Regulatory assets					$ 36,500
RAC
Loss Contingencies [Line Items]
Approved rate, amount	$ 9,700	$ 8,500
NJNG \| RAC
Loss Contingencies [Line Items]
Requested base rate increase (decrease), amount			$ 1,200	$ 1,400