Fair Value Measurements - Level 3 Measurements of Derivative Commodity Instruments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016 USD ($) $ / Mcf $ / bbl
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Derivative liabilities	$ (5,741)
Derivative assets	18,958
Discounted Cash Flow Valuation Technique | Level 3 | Oil Basis - WTI/WTI | 2016
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Derivative liabilities	$ (8,153)
Discounted Cash Flow Valuation Technique | Level 3 | Oil Basis - WTI/WTI | 2016 | Minimum
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Price per barrel | $ / bbl	(0.20)
Discounted Cash Flow Valuation Technique | Level 3 | Oil Basis - WTI/WTI | 2016 | Maximum
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Price per barrel | $ / bbl	(0.43)
Discounted Cash Flow Valuation Technique | Level 3 | Oil Basis - WTS/WTI | 2016
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Derivative liabilities	$ (1,443)
Discounted Cash Flow Valuation Technique | Level 3 | Oil Basis - WTS/WTI | 2016 | Minimum
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Price per barrel | $ / bbl	(0.49)
Discounted Cash Flow Valuation Technique | Level 3 | Oil Basis - WTS/WTI | 2016 | Maximum
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Price per barrel | $ / bbl	(0.69)
Discounted Cash Flow Valuation Technique | Level 3 | Natural Gas Basis - Permian | 2016
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Derivative assets	$ 1,442
Discounted Cash Flow Valuation Technique | Level 3 | Natural Gas Basis - Permian | 2016 | Minimum
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Price per cubic foot | $ / Mcf	(0.17)
Discounted Cash Flow Valuation Technique | Level 3 | Natural Gas Basis - Permian | 2016 | Maximum
Fair Value Inputs, Derivatives, Quantitative Information [Line Items]
Price per cubic foot | $ / Mcf	(0.18)