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DERIVATIVE INSTRUMENTS (Schedule of Derivative Instruments) (Details) | 9 Months Ended
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Sep. 30, 2018 MMBTU $ / bbl $ / MMBTU bbl
NYMEX Henry Hub Swap - 2018 |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 1,010,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 3.01
NYMEX Henry Hub Swap - 2018 | Short | Call Option |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 50,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 3.13
NYMEX Henry Hub Swap - 2019 |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 1,154,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 2.81
NYMEX Henry Hub Swap - 2019 | Short | Call Option |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 30,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 3.10
NYMEX Henry Hub Swap - 2020 |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 204,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 2.77
ARGUS LLS Swap - 2018 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 2,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 56.22
ARGUS LLS Swap - 2019 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 1,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 59.55
NYMEX WTI Swap - 2018 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 4,500
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 53.72
NYMEX WTI Swap - 2019 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 4,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 58.28
Mont Belvieu C2 - 2019 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 1,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 18.48
Mont Belvieu C3 Swap - 2018 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 4,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 29.34
Mont Belvieu C3 Swap - 2019 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 4,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 28.87
Mont Belvieu C5 Swap - 2018 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 500
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 46.62
Mont Belvieu C5 Swap - 2019 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 500
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 54.08
Transco Zone 4 - 2018 | Long |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 40,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 0.05
Transco Zone 4 - 2019 | Long |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 60,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 0.05
Transco Zone 4 - 2020 | Long |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 60,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 0.05

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