United States Operations	6 Months Ended
Jun. 30, 2011
United States Operations [Abstract]
United States Operations	Note 9 — United States Operations In 2008, we initiated a domestic exploration program in two different basins. We are the operator of both exploration programs. Gulf Coast West Bay Project We hold exploration acreage in the Gulf Coast Region of the United States through an Area of Mutual Interest (“AMI”) agreement with two private third parties. During the six months ended June 30, 2011, we and our partners in the West Bay project agreed to relinquish the exploration acreage we held to the farmor. The relinquishment is expected to be completed by August 2011. Neither we nor our partners intend to continue any activity in West Bay. Based on the decision in the second quarter 2011 to relinquish the exploration acreage, we impaired the carrying value of West Bay of $3.3 million as of June 30, 2011. The West Bay project represented $3.3 million of unproved oil and gas properties on our December 31, 2010 balance sheet. Western United States — Antelope On May 17, 2011, we closed the transaction to sell all of our interest in the oil and gas assets located in our Antelope Project area in the Uinta Basin of Utah which consisted of approximately 69,000 gross acres (47,600 net acres), and the related contracts, reserves, production, wells, pipelines production facilities and other rights, title and interests located in the Uintah Basin in Duchesne and Uintah Counties, Utah. The transaction included the Mesaverde Gas Exploration and Appraisal Project (“Mesaverde”), the Lower Green River/Upper Wasatch and the Monument Butte Extension. We owned an approximate working interest of 70 percent in the Mesaverde and Lower Green River/Upper Wasatch, an approximate 60 percent working interest in one well in the Monument Butte Extension, an approximate 43 percent working interest in the initial eight well program in the Monument Butte Extension, and 37 percent working interest in the follow-up six well program in the Monument Butte Extension. The initial eight well program and follow-up six well program in the Monument Butte Extension were non-operated. The sale has an effective date of March 1, 2011 (see Note 3 — Dispositions). We received cash proceeds of approximately $217.8 million which reflects increases to the purchase price for customary adjustments and deductions for transaction related costs. All activities associated with the Antelope Project have been reflected as discontinued operations on the statement of operations.

Note 9 — United States Operations

In 2008, we initiated a domestic exploration program in two different basins. We are the operator of both exploration programs.

Gulf Coast

West Bay Project

We hold exploration acreage in the Gulf Coast Region of the United States through an Area of Mutual Interest (“AMI”) agreement with two private third parties. During the six months ended June 30, 2011, we and our partners in the West Bay project agreed to relinquish the exploration acreage we held to the farmor. The relinquishment is expected to be completed by August 2011. Neither we nor our partners intend to continue any activity in West Bay. Based on the decision in the second quarter 2011 to relinquish the exploration acreage, we impaired the carrying value of West Bay of $3.3 million as of June 30, 2011. The West Bay project represented $3.3 million of unproved oil and gas properties on our December 31, 2010 balance sheet.

Western United States — Antelope

On May 17, 2011, we closed the transaction to sell all of our interest in the oil and gas assets located in our Antelope Project area in the Uinta Basin of Utah which consisted of approximately 69,000 gross acres (47,600 net acres), and the related contracts, reserves, production, wells, pipelines production facilities and other rights, title and interests located in the Uintah Basin in Duchesne and Uintah Counties, Utah. The transaction included the Mesaverde Gas Exploration and Appraisal Project (“Mesaverde”), the Lower Green River/Upper Wasatch and the Monument Butte Extension. We owned an approximate working interest of 70 percent in the Mesaverde and Lower Green River/Upper Wasatch, an approximate 60 percent working interest in one well in the Monument Butte Extension, an approximate 43 percent working interest in the initial eight well program in the Monument Butte Extension, and 37 percent working interest in the follow-up six well program in the Monument Butte Extension. The initial eight well program and follow-up six well program in the Monument Butte Extension were non-operated. The sale has an effective date of March 1, 2011 (see Note 3 — Dispositions). We received cash proceeds of approximately $217.8 million which reflects increases to the purchase price for customary adjustments and deductions for transaction related costs. All activities associated with the Antelope Project have been reflected as discontinued operations on the statement of operations.