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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - GAS IN STORAGE (Details) $ in Thousands | Dec. 31, 2015 USD ($) Bcf | Sep. 30, 2015 USD ($) Bcf
--- | --- | ---
Inventory [Line Items] |  |
Gas in Storage | $ | $ 189,907 | $ 163,905
Bcf | Bcf | 85.0 | 66.0
NJRES [Member] |  |
Inventory [Line Items] |  |
Gas in Storage | $ | $ 119,401 | $ 93,696
Bcf | Bcf | 62.0 | 44.6
NJNG [Member] |  |
Inventory [Line Items] |  |
Gas in Storage | $ | $ 70,506 | $ 70,209
Bcf | Bcf | 23.0 | 21.4

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- Definition Natural Gas in Storage Nonmonetary Number of Billion Cubic Feet of Gas in Storage as of the balance sheet date. + References No definition available. + Details
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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 + Details
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- Details
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- Details
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