Annual report pursuant to Section 13 and 15(d)

Derivative Financial Instruments - Open Commodity Derivatives (Details)

v3.3.1.900
Derivative Financial Instruments - Open Commodity Derivatives (Details)
 12 Months Ended
Dec. 31, 2015
MMBTU
$ / Derivative
bbl
NYMEX Crude Oil - Two-Way Collars  
Derivatives Fair Value [Line Items]  
Notional Quantity (Bbls) | bbl 1,830,000 [1]
NYMEX Crude Oil - Two-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 40.00
NYMEX Crude Oil - Two-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 81.47
NYMEX Natural Gas - Three-Way Collars  
Derivatives Fair Value [Line Items]  
Notional Quantity (MMBTUs) | MMBTU 13,400,000 [1]
NYMEX Natural Gas - Three-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 2.25
NYMEX Natural Gas - Three-Way Collars | Call Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.77
NYMEX Natural Gas - Three-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.50
2016: 1st Quarter | NYMEX Crude Oil - Two-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 1st Quarter
Notional Quantity (Bbls/day) | bbl 5,000 [1]
Notional Quantity (Bbls) | bbl 455,000 [1]
2016: 1st Quarter | NYMEX Crude Oil - Two-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 40.00
2016: 1st Quarter | NYMEX Crude Oil - Two-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 81.47
2016: 1st Quarter | NYMEX Natural Gas - Three-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 1st Quarter [2]
Notional Quantity (MMBTUs/day) | MMBTU 40,000 [1],[2]
Notional Quantity (MMBTUs) | MMBTU 2,400,000 [1],[2]
2016: 1st Quarter | NYMEX Natural Gas - Three-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 2.25 [2]
2016: 1st Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.77 [2]
2016: 1st Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.50 [2]
2016: 2nd Quarter | NYMEX Crude Oil - Two-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 2nd Quarter
Notional Quantity (Bbls/day) | bbl 5,000 [1]
Notional Quantity (Bbls) | bbl 455,000 [1]
2016: 2nd Quarter | NYMEX Crude Oil - Two-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 40.00
2016: 2nd Quarter | NYMEX Crude Oil - Two-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 81.47
2016: 2nd Quarter | NYMEX Natural Gas - Three-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 2nd Quarter
Notional Quantity (MMBTUs/day) | MMBTU 40,000 [1]
Notional Quantity (MMBTUs) | MMBTU 3,640,000 [1]
2016: 2nd Quarter | NYMEX Natural Gas - Three-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 2.25
2016: 2nd Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.77
2016: 2nd Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.50
2016: 3rd Quarter | NYMEX Crude Oil - Two-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 3rd Quarter
Notional Quantity (Bbls/day) | bbl 5,000 [1]
Notional Quantity (Bbls) | bbl 460,000 [1]
2016: 3rd Quarter | NYMEX Crude Oil - Two-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 40.00
2016: 3rd Quarter | NYMEX Crude Oil - Two-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 81.47
2016: 3rd Quarter | NYMEX Natural Gas - Three-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 3rd Quarter
Notional Quantity (MMBTUs/day) | MMBTU 40,000 [1]
Notional Quantity (MMBTUs) | MMBTU 3,680,000 [1]
2016: 3rd Quarter | NYMEX Natural Gas - Three-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 2.25
2016: 3rd Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.77
2016: 3rd Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.50
2016: 4th Quarter | NYMEX Crude Oil - Two-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 4th Quarter
Notional Quantity (Bbls/day) | bbl 5,000 [1]
Notional Quantity (Bbls) | bbl 460,000 [1]
2016: 4th Quarter | NYMEX Crude Oil - Two-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 40.00
2016: 4th Quarter | NYMEX Crude Oil - Two-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 81.47
2016: 4th Quarter | NYMEX Natural Gas - Three-Way Collars  
Derivatives Fair Value [Line Items]  
Termination Period 4th Quarter
Notional Quantity (MMBTUs/day) | MMBTU 40,000 [1]
Notional Quantity (MMBTUs) | MMBTU 3,680,000 [1]
2016: 4th Quarter | NYMEX Natural Gas - Three-Way Collars | Put Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 2.25
2016: 4th Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Bought  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.77
2016: 4th Quarter | NYMEX Natural Gas - Three-Way Collars | Call Option | Sold  
Derivatives Fair Value [Line Items]  
Weighted Average Contract Price 3.50
[1] Volume Measurements: Bbls – barrelsMMBTUs – million British Thermal Units.
[2] The natural gas derivative contracts are priced and closed in the last week prior to the related production month. Natural gas derivative contracts related to January 2016 production were priced and closed in December 2015 and are excluded in the above table as these were closed contracts as of December 31, 2015