Annual report pursuant to Section 13 and 15(d)

Derivative Instruments - Schedule of Derivative Instruments (Details)

v3.8.0.1
Derivative Instruments - Schedule of Derivative Instruments (Details)
 12 Months Ended
Dec. 31, 2017
MMBTU
$ / bbl
$ / MMBTU
bbl
NYMEX Henry Hub Swap - 2018  
Derivative [Line Items]  
Daily Volume (MMBtu/day) | MMBTU 908,000
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU 3.06
NYMEX Henry Hub Swap - 2019  
Derivative [Line Items]  
Daily Volume (MMBtu/day) | MMBTU 269,000
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU 2.93
ARGUS LLS Swap - 2018  
Derivative [Line Items]  
Daily Volume (Bbls/day) | bbl 1,500
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / bbl 56.22
NYMEX WTI Swap - 2018  
Derivative [Line Items]  
Daily Volume (Bbls/day) | bbl 4,000
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / bbl 52.20
Mont Belvieu C3 Swap - 2018  
Derivative [Line Items]  
Daily Volume (Bbls/day) | bbl 3,500
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / bbl 28.03
Mont Belvieu C5 Swap - 2018  
Derivative [Line Items]  
Daily Volume (Bbls/day) | bbl 500
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / bbl 46.62
NYMEX Henry Hub - January 2018 - March 2018 | Call option | Short  
Derivative [Line Items]  
Daily Volume (MMBtu/day) | MMBTU 20,000
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU 2.91
NYMEX Henry Hub Swap - April 2018 to March 2019 | Call option | Short  
Derivative [Line Items]  
Daily Volume (MMBtu/day) | MMBTU 50,000
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU 3.13
NYMEX Henry Hub Swap - April 2019 to December 2019 | Call option | Short  
Derivative [Line Items]  
Daily Volume (MMBtu/day) | MMBTU 30,000
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU 3.10
NPGL Mid-Continent Swap - 2018 | Call option | Short  
Derivative [Line Items]  
Daily Volume (MMBtu/day) | MMBTU 12,000
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU 0.26