Derivative Financial Instruments (Gas Volume And Weighted Average Price) (Details)	12 Months Ended																																																					1 Months Ended		12 Months Ended
	Dec. 31, 2011 2012 - Swap Contracts [Member] Mmbtu		Dec. 31, 2011 2012 - Collar Contracts [Member] Mmbtu	Dec. 31, 2011 2012 - Collar Contracts [Member] Ceiling [Member]	Dec. 31, 2011 2012 - Collar Contracts [Member] Floor [Member]	Dec. 31, 2011 2012 - Collar Contracts With Short Puts [Member] Mmbtu		Dec. 31, 2011 2012 - Collar Contracts With Short Puts [Member] Ceiling [Member]		Dec. 31, 2011 2012 - Collar Contracts With Short Puts [Member] Floor [Member]		Dec. 31, 2011 2012 - Collar Contracts With Short Puts [Member] Short Put [Member]		Dec. 31, 2011 2012 - Basis Swap Contracts [Member] Mmbtu	Dec. 31, 2011 2013 - Swap Contracts [Member] Mmbtu		Dec. 31, 2011 2013 - Collar Contracts [Member] Mmbtu	Dec. 31, 2011 2013 - Collar Contracts [Member] Ceiling [Member]	Dec. 31, 2011 2013 - Collar Contracts [Member] Floor [Member]	Dec. 31, 2011 2013 - Collar Contracts With Short Puts [Member] Mmbtu		Dec. 31, 2011 2013 - Collar Contracts With Short Puts [Member] Ceiling [Member]		Dec. 31, 2011 2013 - Collar Contracts With Short Puts [Member] Floor [Member]		Dec. 31, 2011 2013 - Collar Contracts With Short Puts [Member] Short Put [Member]		Dec. 31, 2011 2013 - Basis Swap Contracts [Member] Mmbtu	Dec. 31, 2011 2014 - Swap Contracts [Member] Mmbtu		Dec. 31, 2011 2014 - Collar Contracts [Member] Mmbtu	Dec. 31, 2011 2014 - Collar Contracts [Member] Ceiling [Member]	Dec. 31, 2011 2014 - Collar Contracts [Member] Floor [Member]	Dec. 31, 2011 2014 - Collar Contracts With Short Puts [Member] Mmbtu		Dec. 31, 2011 2014 - Collar Contracts With Short Puts [Member] Ceiling [Member]		Dec. 31, 2011 2014 - Collar Contracts With Short Puts [Member] Floor [Member]		Dec. 31, 2011 2014 - Collar Contracts With Short Puts [Member] Short Put [Member]		Dec. 31, 2011 2014 - Basis Swap Contracts [Member] Mmbtu	Dec. 31, 2011 2015 - Collar Contracts [Member] Mmbtu	Dec. 31, 2011 2015 - Collar Contracts [Member] Ceiling [Member]	Dec. 31, 2011 2015 - Collar Contracts [Member] Floor [Member]	Dec. 31, 2011 2015 - Collar Contracts With Short Puts [Member] Mmbtu		Dec. 31, 2011 2015 - Collar Contracts With Short Puts [Member] Ceiling [Member]		Dec. 31, 2011 2015 - Collar Contracts With Short Puts [Member] Floor [Member]		Dec. 31, 2011 2015 - Collar Contracts With Short Puts [Member] Short Put [Member]		Jan. 31, 2012 Offsetting Swap Contracts [Member] Mmbtu	Jan. 31, 2012 Additional 2012 Swap Contracts [Member] Mmbtu	Dec. 31, 2011 Additional 2013 Swap Contracts [Member] Mmbtu	Dec. 31, 2011 Additional 2012 Collar Contracts [Member] Mmbtu
Derivative [Line Items]
Volume (MMBtu)	105,000	[1]	65,000			170,000	[1]							136,000	67,500	[1]	150,000			45,000	[1]							142,500	50,000	[1]	140,000			60,000	[1]							115,000	50,000			30,000	[1]							20,000	95,000	45,000	75,000
Price per MMBtu	5.82	[1]		6.60	5.00			7.92	[1]	6.07	[1]	4.50	[1]	(0.34)	6.11	[1]		6.25	5.00			7.49	[1]	6.00	[1]	4.50	[1]	(0.22)	6.05	[1]		6.44	5.00			7.80	[1]	5.83	[1]	4.42	[1]	(0.23)		7.92	5.00			7.11	[1]	5.00	[1]	4.00	[1]	2.41	4.47	4.88	4.41

[1] During the period from January 1, 2012 to February 24, 2012, the Company (i) entered into offsetting swap contracts for 20,000 MMBtus per day of the Company's March 2012 production with a fixed price of $2.41, (ii) converted 95,000 MMBtus per day of the Company's February through December 2012 collar contracts with short puts to swap contracts with a fixed price of $4.47 per MMBtu , (iii) converted 75,000 MMBtus per day of the Company's March through December 2012 collar contracts with short puts to swap contracts with a fixed price of $4.41 per MMBtu and (iii) converted 45,000 MMBtus per day of the Company's 2013 collar contracts with short puts to swap contracts with a fixed price of $4.88 per MMbtu.