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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - GAS IN STORAGE (Details) $ in Thousands | Dec. 31, 2016 USD ($) Bcf | Sep. 30, 2016 USD ($) Bcf
--- | --- | ---
Inventory [Line Items] |  |
Gas in Storage, value | $ | $ 220,097 | $ 206,251
Gas in Storage, Bcf | Bcf | 78.8 | 83.3
NJRES |  |
Inventory [Line Items] |  |
Gas in Storage, value | $ | $ 163,393 | $ 130,493
Gas in Storage, Bcf | Bcf | 62.9 | 62.0
NJNG |  |
Inventory [Line Items] |  |
Gas in Storage, value | $ | $ 56,704 | $ 75,758
Gas in Storage, Bcf | Bcf | 15.9 | 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 + Details
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