Construction Contracts	3 Months Ended
Mar. 31, 2013
Contractors [Abstract]
Construction Contracts	Construction Contracts Century Plant. As of December 31, 2012, the Company had substantially completed construction of a carbon dioxide (“CO₂”) treatment plant in Pecos County, Texas (the “Century Plant”), and associated compression and pipeline facilities pursuant to an agreement with Occidental Petroleum Corporation (“Occidental”). The Company constructed the Century Plant for a contract price of $796.3 million, which included agreed upon change orders and scope revisions, that Occidental paid to the Company through periodic cost reimbursements based upon the percentage of the project completed. Upon substantial completion of construction in late 2012, Occidental took ownership and began operating the Century Plant for the purpose of separating and removing CO₂ from the delivered natural gas stream. The Company recorded additions totaling $180.0 million to its oil and natural gas properties for costs incurred in excess of contract amounts during the construction period. Billings and estimated contract loss in excess of costs incurred of $5.8 million and $15.5 million at March 31, 2013 and December 31, 2012, respectively, representing costs expected to be incurred in the final stages of construction, are reported as a current liability in the accompanying unaudited condensed consolidated balance sheets. Pursuant to a 30-year treating agreement executed simultaneously with the construction agreement, Occidental will remove CO₂ from the Company’s delivered natural gas production volumes. Under this agreement, the Company is required to deliver certain minimum CO₂ volumes annually and is required to compensate Occidental to the extent such requirements are not met. See Note 11 for additional discussion of this contract. The Company retains all methane gas from the natural gas it delivers to the Century Plant. Transmission Expansion Projects. The Company is managing the design, engineering and construction of a series of electrical transmission expansion and upgrade projects in northern Oklahoma. Under the terms of the agreement, the Company will be reimbursed for costs incurred on these projects up to approximately $23.3 million, plus any subsequently agreed-upon revisions. Construction on these projects began in 2012 with the final project expected to be completed in the second quarter of 2013. Costs in excess of billings on these projects of approximately $6.7 million and $11.2 million at March 31, 2013 and December 31, 2012, respectively, are included in current assets in the accompanying unaudited condensed consolidated balance sheets.

Construction Contracts

Century Plant. As of December 31, 2012, the Company had substantially completed construction of a carbon dioxide (“CO₂”) treatment plant in Pecos County, Texas (the “Century Plant”), and associated compression and pipeline facilities pursuant to an agreement with Occidental Petroleum Corporation (“Occidental”). The Company constructed the Century Plant for a contract price of $796.3 million, which included agreed upon change orders and scope revisions, that Occidental paid to the Company through periodic cost reimbursements based upon the percentage of the project completed. Upon substantial completion of construction in late 2012, Occidental took ownership and began operating the Century Plant for the purpose of separating and removing CO₂ from the delivered natural gas stream. The Company recorded additions totaling $180.0 million to its oil and natural gas properties for costs incurred in excess of contract amounts during the construction period. Billings and estimated contract loss in excess of costs incurred of $5.8 million and $15.5 million at March 31, 2013 and December 31, 2012, respectively, representing costs expected to be incurred in the final stages of construction, are reported as a current liability in the accompanying unaudited condensed consolidated balance sheets.

Pursuant to a 30-year treating agreement executed simultaneously with the construction agreement, Occidental will remove CO₂ from the Company’s delivered natural gas production volumes. Under this agreement, the Company is required to deliver certain minimum CO₂ volumes annually and is required to compensate Occidental to the extent such requirements are not met. See Note 11 for additional discussion of this contract. The Company retains all methane gas from the natural gas it delivers to the Century Plant.

Transmission Expansion Projects. The Company is managing the design, engineering and construction of a series of electrical transmission expansion and upgrade projects in northern Oklahoma. Under the terms of the agreement, the Company will be reimbursed for costs incurred on these projects up to approximately $23.3 million, plus any subsequently agreed-upon revisions. Construction on these projects began in 2012 with the final project expected to be completed in the second quarter of 2013. Costs in excess of billings on these projects of approximately $6.7 million and $11.2 million at March 31, 2013 and December 31, 2012, respectively, are included in current assets in the accompanying unaudited condensed consolidated balance sheets.