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NATURE OF THE BUSINESS (Details) shares in Thousands	9 Months Ended
	Jun. 30, 2016 subsidiary customer shares
Common Units [Member]
Nature of Business [Line Items]
Ownership interest exchanged (in shares) | shares	1,840
Steckman Ridge [Member]
Nature of Business [Line Items]
Equity method investment, ownership percentage	50.00%
PennEast [Member]
Nature of Business [Line Items]
Equity method investment, ownership percentage	20.00%
NJNG [Member]
Nature of Business [Line Items]
Total retail customers | customer	519,800
NJR Retail Holdings Corporation [Member]
Nature of Business [Line Items]
Number of principal subsidiaries | subsidiary	2

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Number of Principal Subsidiaries

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Total number of retail customers specific to NJNG

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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The number of units of other ownership interests issued in a limited partnership or master limited partnership. Does not include limited or general partners' ownership interests.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

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