Number of First Mortgage Bond

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- Definition

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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- Definition

Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

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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- Definition

The cash inflow from amounts received from a long-term debt instrument secured by a first mortgage deed of trust, containing a pledge of real property. The lender has the highest claim on the property in case of default.

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- Definition

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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Other amounts the seller-lessee is required to pay under the terms of the transaction involving the sale of property to another party and lease of the property back to the seller, including reimbursements for such items, as utilities, taxes, insurance and common area maintenance.

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DEBT - LONG TERM DEBT (Details)		1 Months Ended		3 Months Ended	9 Months Ended
DEBT - LONG TERM DEBT (Details)	Apr. 18, 2019 USD ($) First_mortgage_bond	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Aug. 15, 2019 USD ($)	Jul. 17, 2019 USD ($)
Debt Instrument [Line Items]
Proceeds from sale-leaseback transaction					$ 9,895,000	$ 7,820,000
NJNG
Debt Instrument [Line Items]
Proceeds from sale-leaseback transaction		$ 9,900,000	$ 7,800,000
Remaining principal payments				$ 1,100,000		$ 1,100,000
Number of first mortgage bonds \| First_mortgage_bond	3
Proceeds from reissuance of first mortgage bond	$ 35,800,000
NJNG \| First Mortgage Bond
Debt Instrument [Line Items]
Weighted average interest rate	3.02%
NJR \| Unsecured Senior Note \| Scenario, Forecast
Debt Instrument [Line Items]
Debt issued							$ 100,000,000
Subsequent Event \| NJNG \| Unsecured Senior Note 3.76%
Debt Instrument [Line Items]
Debt issued								$ 100,000,000
Interest rate, stated percentage								3.76%
Subsequent Event \| NJNG \| Unsecured Senior Note 3.86%
Debt Instrument [Line Items]
Debt issued								$ 85,000,000
Interest rate, stated percentage								3.86%
Subsequent Event \| NJR \| Unsecured Senior Note
Debt Instrument [Line Items]
Debt issued								$ 50,000,000
Interest rate, stated percentage								3.29%