Line of Credit Facility, Issuance period

No definition available.

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- Definition

Number of Debt Instruments

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Period Type:	instant

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 55

-Paragraph 51

-URI http://asc.fasb.org/extlink&oid=28365400&loc=d3e51840-112757

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-Topic 840

-SubTopic 40

-Section 55

-Paragraph 52

-URI http://asc.fasb.org/extlink&oid=28365400&loc=d3e51843-112757

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- Details

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DEBT - SCHEDULE OF LONG TERM DEBT (Details)		1 Months Ended		9 Months Ended
DEBT - SCHEDULE OF LONG TERM DEBT (Details)	Sep. 26, 2013 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Jun. 30, 2015 USD ($) note	Jun. 30, 2014 USD ($)	Apr. 15, 2015 USD ($)	Nov. 07, 2014 USD ($)	Mar. 13, 2014 USD ($)
Debt Instrument [Line Items]
Proceeds from sale-leaseback transaction				$ 7,216,000	$ 7,576,000
NJR [Member] \| Debt Shelf Facility Prudential [Member] \| Unsecured Senior Note 3.25% [Member]
Debt Instrument [Line Items]
Amount issued and outstanding				$ 50,000,000
Interest rate, stated percentage				3.25%
NJR [Member] \| Debt Shelf Facility Prudential [Member] \| Unsecured Senior Note 3.48% [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage							3.48%
Debt issued							$ 100,000,000
NJR [Member] \| Debt Shelf Facility Metlife 2 [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 100,000,000
Line of credit facility, issuance period	3 years
Line of credit facility, remaining borrowing capacity				$ 100,000,000
NJR [Member] \| Debt Shelf Facility Metlife [Member] \| Unsecured Senior Note 1.94% [Member]
Debt Instrument [Line Items]
Amount issued and outstanding				$ 25,000,000
Interest rate, stated percentage				1.94%
Number of debt instruments outstanding \| note				2
NJR [Member] \| Debt Shelf Facility Metlife [Member] \| Unsecured Senior Note 2.51% [Member]
Debt Instrument [Line Items]
Amount issued and outstanding				$ 25,000,000
Interest rate, stated percentage				2.51%
NJNG [Member]
Debt Instrument [Line Items]
Proceeds from sale-leaseback transaction		$ 7,200,000	$ 7,600,000
NJNG [Member] \| First Mortgage [Member] \| 2.82% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage						2.82%
Debt issued						$ 50,000,000
NJNG [Member] \| First Mortgage [Member] \| 3.66% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage						3.66%
Debt issued						$ 100,000,000
NJNG [Member] \| First Mortgage [Member] \| 3.58% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage								3.58%
Debt issued								$ 70,000,000
NJNG [Member] \| First Mortgage [Member] \| 4.61% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage								4.61%
Debt issued								$ 55,000,000