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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - GAS IN STORAGE (Details) $ in Thousands | Jun. 30, 2015 USD ($) Bcf | Sep. 30, 2014 USD ($) Bcf
--- | --- | ---
Inventory [Line Items] |  |
Gas in Storage | $ 117,115 | $ 277,516
Gas in Storage (Bcf) | Bcf | 48.7 | 77.8
NJRES [Member] |  |
Inventory [Line Items] |  |
Gas in Storage | $ 81,829 | $ 191,250
Gas in Storage (Bcf) | Bcf | 36.6 | 56.5
NJNG [Member] |  |
Inventory [Line Items] |  |
Gas in Storage | $ 35,286 | $ 86,266
Gas in Storage (Bcf) | Bcf | 12.1 | 21.3

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- Definition Carrying amount as of the balance sheet date of natural gas in storage, which is a mixture of gases (liquefied or otherwise), used for fuel and manufacturing purposes, which is ready for sale. + 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 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 6 -Subparagraph a -Article 5 + Details
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