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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

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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COMMITMENTS AND CONTINGENT LIABILITIES - LEGAL PROCEEDINGS (Details) $ in Thousands	1 Months Ended	9 Months Ended	18 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2015 USD ($) site	May. 31, 2015 USD ($)	Sep. 30, 2014 USD ($)
Site Contingency [Line Items]
Recovery of expenditures, including carrying costs, rolling period approved by the BPU		7 years
Regulatory assets	$ 351,763	$ 351,763		$ 377,575
Number of MGP sites \| site		5
Minimum [Member]
Site Contingency [Line Items]
Litigation settlement, gross		$ 151,300
Maximum [Member]
Site Contingency [Line Items]
Litigation settlement, gross		249,800
Environmental Remediation Costs Expended, Net of Recoveries [Member]
Site Contingency [Line Items]
Regulatory assets	18,095	18,095		30,916
Environmental Remediation Costs Liability for Future Expenditures [Member]
Site Contingency [Line Items]
Regulatory assets	177,000	$ 177,000		$ 177,000
RA [Member] \| July 2013 SBC Filing [Member]
Site Contingency [Line Items]
Reduction in the RA factor			$ 18,700
RA [Member] \| September 2014 SBC Filing [Member]
Site Contingency [Line Items]
Reduction in the RA factor	$ 8,500