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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - GAS IN STORAGE (Details) $ in Thousands | Mar. 31, 2018 USD ($) Bcf | Sep. 30, 2017 USD ($) Bcf
--- | --- | ---
Inventory [Line Items] |  |
Gas in Storage, value | $ | $ 71,169 | $ 202,063
Gas in Storage, Bcf | Bcf | 23.3 | 75.7
Energy Services |  |
Inventory [Line Items] |  |
Gas in Storage, value | $ | $ 51,915 | $ 122,884
Gas in Storage, Bcf | Bcf | 18.6 | 53.9
Natural Gas Distribution |  |
Inventory [Line Items] |  |
Gas in Storage, value | $ | $ 19,254 | $ 79,179
Gas in Storage, Bcf | Bcf | 4.7 | 21.8

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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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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