COMMON STOCK EQUITY - DIVIDEND REINVESTMENT PLAN (Details) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Equity [Abstract]
Equity raised through the DRP	$ 7.7	$ 7.4
Number of treasury shares issued from raising of equity through the DRP	152,000	163,000
Additional equity raised	$ 19.8
Additional shares issued through the waiver discount feature of the DRP	344,000	0

Number of shares issued during the period from a DRP waiver discount feature.

No definition available.

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- Definition

Value of stock issued during the period from a DRP waiver discount feature. NJR can waive the $100,000 limit on initial and optional cash investments upon request by an investor and offer a discount up to 3%.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of cash inflow from capital contributions to an entity associated with a dividend reinvestment plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

+ Details

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