Derivative Instruments and Hedging Activities (Details)	3 Months Ended
	Mar. 31, 2014
Crude Oil Commodity Contract | Swaps - NYMEX WTI 2014
Derivative [Line Items]
Period	2014
Index	NYMEX WTI	[1]
Volume Per Day	37,000
Weighted Average Fixed Price	92.67
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract | Swaps - Dated Brent 2014
Derivative [Line Items]
Period	2014
Index	Dated Brent
Volume Per Day	13,000
Weighted Average Fixed Price	103.21
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract | Three Way Collars - NYMEX WTI 2014
Derivative [Line Items]
Period	2014
Index	NYMEX WTI	[1]
Volume Per Day	12,000
Weighted Average Fixed Price
Weighted Average Short Put Price	75.67
Weighted Average Floor Price	90.67
Weighted Average Ceiling Price	100.88
Crude Oil Commodity Contract | Three Way Collars - Dated Brent 2014
Derivative [Line Items]
Period	2014
Index	Dated Brent
Volume Per Day	8,000
Weighted Average Fixed Price	0.00
Weighted Average Short Put Price	84.38
Weighted Average Floor Price	98.25
Weighted Average Ceiling Price	121.56
Crude Oil Commodity Contract | Swaps - NYMEX WTI 2015
Derivative [Line Items]
Period	2015
Index	NYMEX WTI	[1]
Volume Per Day	21,000
Weighted Average Fixed Price	88.05
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract | Swaps - Dated Brent 2015
Derivative [Line Items]
Period	2015
Index	Dated Brent
Volume Per Day	9,000
Weighted Average Fixed Price	100.16
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract | Three Way Collars - NYMEX WTI 2015
Derivative [Line Items]
Period	2015
Index	NYMEX WTI	[1]
Volume Per Day	18,000
Weighted Average Fixed Price
Weighted Average Short Put Price	70.56
Weighted Average Floor Price	87.50
Weighted Average Ceiling Price	94.34
Crude Oil Commodity Contract | Three Way Collars - Dated Brent 2015
Derivative [Line Items]
Period	2015
Index	Dated Brent
Volume Per Day	13,000
Weighted Average Fixed Price
Weighted Average Short Put Price	76.92
Weighted Average Floor Price	96.00
Weighted Average Ceiling Price	108.49
Crude Oil Commodity Contract | Swaps - Dated Brent 2016
Derivative [Line Items]
Period	2016
Index	Dated Brent
Volume Per Day	4,000
Weighted Average Fixed Price	95.84
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Crude Oil Commodity Contract | Three Way Collars - Dated Brent 2016
Derivative [Line Items]
Period	2016
Index	Dated Brent
Volume Per Day	6,000
Weighted Average Fixed Price
Weighted Average Short Put Price	80.00
Weighted Average Floor Price	95.00
Weighted Average Ceiling Price	105.87
Natural Gas Commodity Contract | Swaps - NYMEX HH 2014
Derivative [Line Items]
Period	2014
Index	NYMEX HH	[2]
Volume Per Day	60,000
Weighted Average Fixed Price	4.24
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Natural Gas Commodity Contract | Three Way Collar - NYMEX HH 2014
Derivative [Line Items]
Period	2014
Index	NYMEX HH	[2]
Volume Per Day	230,000
Weighted Average Fixed Price
Weighted Average Short Put Price	2.83
Weighted Average Floor Price	3.75
Weighted Average Ceiling Price	4.98
Natural Gas Commodity Contract | Swaps - NYMEX HH 2015
Derivative [Line Items]
Period	2015
Index	NYMEX HH	[2]
Volume Per Day	110,000
Weighted Average Fixed Price	4.30
Weighted Average Short Put Price
Weighted Average Floor Price
Weighted Average Ceiling Price
Natural Gas Commodity Contract | Three Way Collars - NYMEX HH 2015
Derivative [Line Items]
Period	2015
Index	NYMEX HH	[2]
Volume Per Day	120,000
Weighted Average Fixed Price
Weighted Average Short Put Price	3.54
Weighted Average Floor Price	4.25
Weighted Average Ceiling Price	5.06

[1] West Texas Intermediate

[2] Henry Hub