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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - GAS IN STORAGE (Details) $ in Thousands | Sep. 30, 2020 USD ($) Bcf | Sep. 30, 2019 USD ($) Bcf
--- | --- | ---
Public Utilities, Inventory [Line Items] |  |
Natural Gas in Storage | $ | $ 167,504 | $ 169,803
Bcf | Bcf | 61.52 | 52.6
Natural Gas Distribution |  |
Public Utilities, Inventory [Line Items] |  |
Natural Gas in Storage | $ | $ 110,037 | $ 117,413
Bcf | Bcf | 27.2 | 27.0
Energy Services |  |
Public Utilities, Inventory [Line Items] |  |
Natural Gas in Storage | $ | $ 57,352 | $ 52,390
Bcf | Bcf | 34.3 | 25.6
Storage and Transportation |  |
Public Utilities, Inventory [Line Items] |  |
Natural Gas in Storage | $ | $ 115 | $ 0
Bcf | Bcf | 0.02 | 0

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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://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&loc=d3e13212-122682 + Details
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