Construction Contracts - Additional Information (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Construction Contracts [Line Items]
Estimated loss identified based on projections of the costs to be incurred in excess of contract amounts, during period	$ (50,000,000)	$ (25,000,000)	$ (105,000,000)
Billings and estimated contract loss in excess of costs incurred	15,546,000	43,320,000
Century Plant
Construction Contracts [Line Items]
Construction agreement description	The Company has substantially completed construction of the Century Plant and associated compression and pipeline facilities pursuant to an agreement with Occidental. Under the terms of the agreement, the Company constructed the Century Plant for a contract price of $796.3 million, including subsequently agreed upon change orders and scope revisions, payable through periodic cost reimbursements based upon the percentage of the project completed by the Company. During 2012, both phases of construction were substantially completed and Occidental took ownership and began operating the plant for the purpose of separating and removing CO2 from the delivered natural gas stream. With the completion of the contract, the Company recorded construction contract revenue and construction contract costs equal to the revised contract price of $796.3 million, which are included in the accompanying consolidated statements of operations.
Construction contract price	796,300,000
Estimated loss identified based on projections of the costs to be incurred in excess of contract amounts, total	180,000,000
Estimated loss identified based on projections of the costs to be incurred in excess of contract amounts, during period	(50,000,000)	(25,000,000)
Billings and estimated contract loss in excess of costs incurred	15,546,000	43,320,000
Treating agreement contract term	30 years
Transmission Expansion Projects
Construction Contracts [Line Items]
Construction agreement description	The Company entered into a construction services agreement in November 2011 to manage the design, engineering and construction of a series of 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 first quarter of 2013.
Expected construction completion year	2013
Costs in excess of billings	11,200,000	0
Transmission Expansion Projects \| Maximum
Construction Contracts [Line Items]
Construction contract price	$ 23,300,000

Estimated loss identified based on projections of the costs to be incurred in excess of contract amounts, during period

$ (50,000,000)

$ (25,000,000)

$ (105,000,000)

The Company has substantially completed construction of the Century Plant and associated compression and pipeline facilities pursuant to an agreement with Occidental. Under the terms of the agreement, the Company constructed the Century Plant for a contract price of $796.3 million, including subsequently agreed upon change orders and scope revisions, payable through periodic cost reimbursements based upon the percentage of the project completed by the Company. During 2012, both phases of construction were substantially completed and Occidental took ownership and began operating the plant for the purpose of separating and removing CO2 from the delivered natural gas stream. With the completion of the contract, the Company recorded construction contract revenue and construction contract costs equal to the revised contract price of $796.3 million, which are included in the accompanying consolidated statements of operations.

Estimated loss identified based on projections of the costs to be incurred in excess of contract amounts, total

180,000,000

Billings and estimated contract loss in excess of costs incurred

15,546,000

43,320,000

Construction agreement description

The Company entered into a construction services agreement in November 2011 to manage the design, engineering and construction of a series of 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 first quarter of 2013.

Costs in excess of billings

11,200,000

0

Construction Contracts [Line Items]