Derivative Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Commodity Derivatives [Abstract]
Realized (loss) gain on commodity derivatives - natural gas	$ (7,114)	$ 0
Realized (loss) gain on commodity derivatives - crude oil	(1,840)	0
Unrealized Gain (Loss) on Derivatives	(36,319)	(44,715)
Gain loss on commodity derivatives	(45,273)	(44,715)
Swap [Member] | Nymex WTI [Member] | Calendar 2014 [Member]
Schedule Of Derivative Instruments [Line Items]
Volume per day	4,000
Average Price	93.19
Fair Value	(4,997)
Swap [Member] | Nymex Henry Hub [Member] | Fall 2014 [Member]
Schedule Of Derivative Instruments [Line Items]
Volume per day	85,000
Average Price	4.35
Fair Value	(1,074)
Swap [Member] | Nymex Henry Hub [Member] | Summer 2014 [Member]
Schedule Of Derivative Instruments [Line Items]
Volume per day	480,000
Average Price	3.9
Fair Value	$ (56,125)