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NATURE OF THE BUSINESS (Details)	3 Months Ended
	Dec. 31, 2018 subsidiary customer
Steckman Ridge
Nature of Business [Line Items]
Ownership percentage	50.00%
PennEast
Nature of Business [Line Items]
Ownership percentage	20.00%
Natural Gas Distribution
Nature of Business [Line Items]
Total retail customers | customer	543,800
NJR Retail Holdings Corporation
Nature of Business [Line Items]
Number of principal subsidiaries | subsidiary	2

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- Definition

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+ References

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- Definition

Number of Principal Subsidiaries

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- Definition

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+ References

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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