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DERIVATIVE INSTRUMENTS (Narrative) (Details) MMBTU in Thousands, $ in Thousands |  | 1 Months Ended | 9 Months Ended
--- | --- | --- | ---
Nov. 06, 2020 USD ($) MMBTU $ / MMBTU | Oct. 30, 2020 USD ($) MMBTU | Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($)
Derivative [Line Items] |  |  |  |
Net cash receipts on settled derivative instruments | $ |  |  | $ 225,364 | $ 80,744
Subsequent Event |  |  |  |
Derivative [Line Items] |  |  |  |
Daily volume (in MMBtu) | MMBTU | 475 |  |  |
Net cash receipts on settled derivative instruments | $ | $ 60,200 | $ 200 |  |
Strike price | $ / MMBTU | 2.90 |  |  |
2020 | Subsequent Event |  |  |  |
Derivative [Line Items] |  |  |  |
Daily volume (in MMBtu) | MMBTU |  | 40 |  |

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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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- Definition Nominal energy measure used to calculate payments on a derivative instrument. + References No definition available. + Details
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- Definition The strike price on the price risk option contract such as a put option or a call option. + References No definition available. + Details
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- Details
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- Details
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