Derivative Financial Instruments (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($) MMBTU $ / MMBTU	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) MMBTU $ / MMBTU	Jun. 30, 2014 USD ($)
Commodity Derivatives [Abstract]
Realized (loss) gain on commodity derivatives - natural gas	$ 52,625	$ (33,729)	$ 81,984	$ (40,843)
Realized (loss) gain on commodity derivatives - crude oil	0	(3,562)	0	(5,402)
Unrealized Gain (Loss) on Derivatives	(56,271)	22,189	(48,765)	(14,130)
Gain loss on commodity derivatives	$ (3,646)	$ (15,102)	$ 33,219	$ (60,375)
Swap [Member] | Nymex Henry Hub [Member] | Summer 2015 [Member]
Schedule Of Derivative Instruments [Line Items]
Volume per day | MMBTU	672,500		672,500
Average Price | $ / MMBTU	3.5		3.5
Fair Value	$ 55,425		$ 55,425