Commodity Price Risk Management (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013 bbl
Current Asset [Member] | Crude Oil Costless Collars [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets, Fair Value	$ 62
Current Liability [Member] | Crude Oil Costless Collars [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities, Fair Value	$ 647
Crude Oil Costless Collar 10/01/12 - 09/30/13 [Member]
Derivative [Line Items]
Counterparty	BNP Paribas
Basis	WTI
Quantity (barrels per day)	200
Crude Oil Costless Collar 10/01/12 - 09/30/13 [Member] | Put Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	95.00
Crude Oil Costless Collar 10/01/12 - 09/30/13 [Member] | Call Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	117
Crude Oil Costless Collar 07/01/13 - 09/30/13 [Member]
Derivative [Line Items]
Counterparty	Wells Fargo
Basis	WTI
Quantity (barrels per day)	400
Crude Oil Costless Collar 07/01/13 - 09/30/13 [Member] | Put Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	90.00
Crude Oil Costless Collar 07/01/13 - 09/30/13 [Member] | Call Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	97.50
Crude Oil Costless Collar 10/01/13 - 12/31/13 [Member]
Derivative [Line Items]
Counterparty	Wells Fargo
Basis	WTI
Quantity (barrels per day)	600
Crude Oil Costless Collar 10/01/13 - 12/31/13 [Member] | Put Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	90.00
Crude Oil Costless Collar 10/01/13 - 12/31/13 [Member] | Call Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	97.50
Crude Oil Costless Collar 01/01/14 - 06/30/14 [Member]
Derivative [Line Items]
Counterparty	Wells Fargo
Basis	WTI
Quantity (barrels per day)	300
Crude Oil Costless Collar 01/01/14 - 06/30/14 [Member] | Put Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	90.00
Crude Oil Costless Collar 01/01/14 - 06/30/14 [Member] | Call Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	95.00
Crude Oil Costless Collar 01/01/14 - 06/30/14 (2) [Member]
Derivative [Line Items]
Counterparty	Wells Fargo
Basis	WTI
Quantity (barrels per day)	300
Crude Oil Costless Collar 01/01/14 - 06/30/14 (2) [Member] | Put Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	90.00
Crude Oil Costless Collar 01/01/14 - 06/30/14 (2) [Member] | Call Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	97.25
Crude Oil Costless Collar 07/01/14 - 12/31/14 [Member]
Derivative [Line Items]
Counterparty	Wells Fargo
Basis	WTI
Quantity (barrels per day)	300
Crude Oil Costless Collar 07/01/14 - 12/31/14 [Member] | Put Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	90.00
Crude Oil Costless Collar 07/01/14 - 12/31/14 [Member] | Call Option [Member]
Derivative [Line Items]
Strike Price (in dollars per barrel)	98.40