REGULATION, REGULATORY ASSETS AND LIABILITIES (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Regulatory Assets And Liabilities [Line Items]
Regulatory assets current	$ 26,862	$ 34,372
Regulatory assets, noncurrent	377,575	402,202
Regulatory liabilities, current	6,072	1,456
Regulatory liability, noncurrent	61,326	79,647
Conservation Incentive Program [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory liabilities, current	5,752	0
Derivatives, Net, Current [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory liabilities, current	320	1,456
Cost of Removal Obligation [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory liability, noncurrent	61,163	79,315
Derivatives, Net, Noncurrent [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory liability, noncurrent	57	0
Other Noncurrent Regulatory Liabilities [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory liability, noncurrent	106	332
Underrecovered Gas Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets current	12,577	953
Conservation Incentive Program [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets current	0	18,887
New Jersey Clean Energy Program [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets current	14,285	14,532
Enviromental Remediation Costs Expended, Net of Recoveries [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	30,916	46,968
Enviromental Remediation Costs Liability for Future Expenditures [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	177,000	183,600
Deferred Income and Other Taxes [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	9,968	10,718
Derivatives, Net, Noncurrent [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	0	19
SAVEGREEN [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	29,180	30,004
Other Noncurrent Regulatory Assets [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	108,507	101,415
Deferred Superstorm Sandy Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	15,207	14,822
Other Regulatory Asset Noncurrent [Member]
Regulatory Assets And Liabilities [Line Items]
Regulatory assets, noncurrent	$ 6,797	$ 14,656

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

+ References

+ Details

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- Definition

The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 405

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ 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 210.5-02.24)

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

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