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DERIVATIVE INSTRUMENTS (Narrative) (Details) - 2019 | 9 Months Ended
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Sep. 30, 2018 MMBTU $ / MMBTU
Derivative [Line Items] |
Daily volume (in MMBtu) | MMBTU | 100,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 3.05

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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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Namespace Prefix: | us-gaap_
Data Type: | num:energyItemType
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Period Type: | duration

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- Definition Average fixed price related to the group of price risk swap derivatives. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | us-types:perUnitItemType
Balance Type: | na
Period Type: | instant

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |