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The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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Fixed interest rate related to the interest rate derivative.

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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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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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Nominal or face amount used to calculate payment on derivative.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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DERIVATIVE INSTRUMENTS - ADDITIONAL INFORMATION (Details) certificate in Thousands, $ in Millions	Jun. 30, 2020 USD ($) certificate	Jan. 31, 2018 USD ($)
Derivative [Line Items]
Derivative, net liability position, aggregate fair value	$ 15.9
Additional collateral, aggregate fair value	15.9
Foreign currency contracts
Derivative [Line Items]
Notional amount	6.4
Treasury Lock
Derivative [Line Items]
Notional amount	195.0
Treasury Lock \| NJNG
Derivative [Line Items]
Notional amount	$ 60.0
Physical commodity contracts \| Energy Services
Derivative [Line Items]
Number of SRECs \| certificate	(1,276)
Home Services and Other \| Term Loan \| Credit Agreement Due August 16, 2019 \| Interest rate swap
Derivative [Line Items]
Debt issued		$ 100.0
Benchmark interest rate		2.84%