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Derivative Instruments (Schedule of Derivative Instruments) (Details) | Mar. 31, 2018 MMBTU $ / bbl $ / MMBTU bbl
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NYMEX Henry Hub Swap - 2018 |
Derivative [Line Items] |
Daily Volume (MMBtu/day) | MMBTU | 927,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 3.02
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 | 647,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU | 2.84
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 | 45,000
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 | 4,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 53.99
NYMEX WTI Swap - 2019 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 3,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 57.62
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 | 28.97
Mont Belvieu C3 Swap - 2019 |
Derivative [Line Items] |
Daily Volume (Bbls/day) | bbl | 1,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl | 27.05
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

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