Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended				3 Months Ended	6 Months Ended
	Jun. 30, 2013 acre	Jun. 30, 2013 acre	Aug. 01, 2012 acre	May 15, 2008	Aug. 08, 2013 Subsequent Event [Member]	Jun. 30, 2013 Lease agreements [Member]	Jun. 30, 2013 Lease agreements [Member]	Dec. 31, 2012 Lease agreements [Member] Area of Land [Member] Maximum [Member] sqft
Commitments and Contingencies (Textual) [Abstract]
Office space of headquarters								40,071
Lease period		Jun. 30, 2022
Maximum termination outstanding obligations of contracts	$ 2.0	$ 2.0			$ 2.7
Transportation and processing fee under the agreement						1.0	1.8
Commitments and Contingencies (Additional Textual) [Abstract]
Natural gas processing and transportation agreement		5 years
Minimum delivery commitment to avoid paying gas deficiency fee		80.00%
Percentage of minimum delivery commitment to anticipated production		80.00%
Undiscounted minimum commitments	13.7	13.7
Minimum outstanding commitments	6.6	6.6
Issue on the deep rights below the Cotton Valley formation	1,805	1,805
Right to participate in working capital	25.00%	25.00%
Company's total revenue and overriding royalty interests on the acreage range Minimum	2.00%	2.00%
Company's total revenue and overriding royalty interests on the acreage range Maximum	23.00%	23.00%
Loss contingency, lawsuit filing date		May 15, 2008
Royalty owner undivided interest in mineral				0.167
Acres reformed by court			169
Rights on remaining acres			1,636
Consent to the proposed assignment	50.00%
Percentage of costs assumed	100.00%
The amount recovered from company	100.00%
Remittance submitted to company	$ 8.7	$ 8.7
Lease expiring period	Jun. 30, 2022