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- Definition

Sale Leaseback Transaction, Net Proceeds, Financing Activities, Solar

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- Definition

Sale Leaseback Transaction, Term Of Lease

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- Definition

Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in financing activities.

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DEBT - LONG TERM DEBT (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
DEBT - LONG TERM DEBT (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2020	Jun. 30, 2019	Jul. 23, 2020	May 14, 2020	Apr. 29, 2020
Debt Instrument [Line Items]
Proceeds from sale-leaseback transaction					$ 9,895,000
Proceeds from sale-leaseback transaction - solar	$ 42,900,000			$ 42,927,000	0
Clean Energy Ventures \| Minimum
Debt Instrument [Line Items]
Sale leaseback transaction lease term				5 years
Clean Energy Ventures \| Maximum
Debt Instrument [Line Items]
Sale leaseback transaction lease term				15 years
NJNG
Debt Instrument [Line Items]
Proceeds from sale-leaseback transaction		$ 4,000,000	$ 9,900,000
Final principal payments for early purchase options				$ 1,200,000	$ 1,100,000
NJNG \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued							$ 125,000,000
NJNG \| Fixed Interest Rate Maturing 2050 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued	$ 50,000,000			$ 50,000,000			$ 100,000,000
Debt instrument interest rate	3.13%			3.13%			3.13%
NJNG \| Fixed Interest Rate Maturing 2060 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued							$ 25,000,000
Debt instrument interest rate							3.33%
NJR \| Treasury Lock
Debt Instrument [Line Items]
Accumulated other comprehensive loss, net of tax								$ 2,500,000
NJR \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued							$ 260,000,000
NJR \| Fixed Interest Rate Maturing 2030 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued							$ 130,000,000
Debt instrument interest rate							3.50%
NJR \| Fixed Interest Rate Maturing 2032 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued							$ 130,000,000
Debt instrument interest rate							3.60%
Subsequent Event \| NJNG \| Fixed Interest Rate Maturing 2050 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued						$ 50,000,000
Debt instrument interest rate						3.13%
Subsequent Event \| NJNG \| Fixed Interest Rate Maturing 2060 \| Senior Notes
Debt Instrument [Line Items]
Long-term debt issued						$ 25,000,000
Debt instrument interest rate						3.33%