Discontinued Operations Narrative (Details) (USD $)	3 Months Ended	12 Months Ended										1 Months Ended	3 Months Ended
	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Natural Gas Reserves MMcf	Dec. 31, 2012 Natural Gas Reserves MMcf	Dec. 31, 2011 Natural Gas Reserves MMcf	Dec. 31, 2013 Oil Reserves MBbls	Dec. 31, 2012 Oil Reserves MBbls	Dec. 31, 2011 Oil Reserves MBbls	Dec. 31, 2012 Black Warrior Basin Natural Gas Reserves MMcf	Oct. 31, 2013 Black Warrior Basin Alabama	Dec. 31, 2013 Black Warrior Basin Alabama	Dec. 31, 2013 North Louisiana/East Texas	Sep. 30, 2013 North Louisiana/East Texas	Jan. 31, 2014 North Louisiana/East Texas Subsequent Event	Dec. 31, 2012 North Louisiana/East Texas Natural Gas Reserves MMcf	Dec. 31, 2012 North Louisiana/East Texas Oil Reserves bbl
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash received from sale of oil properties												$ 160,000,000
Gain on sale of oil and gas property													35,000,000
Proved developed reserves at end of period (volume)					623,305	708,657	788,812	113,795	105,976	83,899	0						0	0
Sales price																31,500,000
Impairments of oil and gas property														5,200,000	24,600,000
Asset impairment	$ 21,500,000	$ 29,794,000	$ 21,545,000	$ 0