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DERIVATIVE INSTRUMENTS (Schedule of Notional Amounts of Outstanding Derivatives) (Details) - Designated as Hedging Instrument [Member] gal in Millions, MMcf in Millions | 3 Months Ended
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Sep. 30, 2019 gal MMcf | Dec. 31, 2018 gal MMcf
Natural Gas [Member] |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Volume | MMcf | 7.0 | 1.8
Diesel [Member] |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Volume | gal | 2.4 | 11.0

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- Definition Nominal volume used to calculate payments on a derivative instrument. + References No definition available. + Details
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- Details
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- Details
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- Details
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