Divestitures and Assets Held for Sale	12 Months Ended
Dec. 31, 2011
Divestitures and Assets Held for Sale Disclosure [Abstract]
Divestitures and Assets Held for Sale	Note 3 – Divestitures and Assets Held for Sale Eagle Ford Shale Divestiture In August 2011, the Company divested of certain operated Eagle Ford shale assets located in its South Texas & Gulf Coast region. This divestiture was comprised of the Company's entire operated acreage in LaSalle County, Texas, as well as an immaterial adjacent block of its operated acreage in Dimmit County, Texas. Total divestiture proceeds were $230.8 million. The estimated gain on this divestiture was $194.6 million. The final divestiture proceeds are subject to normal post-closing adjustments and are expected to be finalized during the first quarter of 2012. Mid-Continent Divestiture In June 2011, the Company divested of certain non-strategic assets located in its Mid-Continent region. Total divestiture proceeds were $35.8 million. The estimated gain on this divestiture was $28.5 million. The final divestiture proceeds are subject to normal post-closing adjustments and are expected to be finalized during the first quarter of 2012. Rocky Mountain Divestiture In January 2011, the Company divested of certain non-strategic assets located in its Rocky Mountain region. Total divestiture proceeds were $45.5 million. The final gain on this divestiture was $27.2 million. Permian Divestiture In December 2010, the Company completed the divestiture of certain non-strategic assets located in its Permian region. Total divestiture proceeds were $54.7 million. The final gain on this divestiture was $18.4 million. Legacy Divestiture In February 2010, the Company completed the divestiture of certain non-strategic assets located in its Rocky Mountain region. Total divestiture proceeds were $125.3 million. The final gain on this divestiture was $66.7 million. A portion of the transaction was structured to qualify as a like-kind exchange under Section 1031 of the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”). Sequel Divestiture In March 2010, the Company completed the divestiture of certain non-strategic assets located in its Rocky Mountain region. Total divestiture proceeds were $129.1 million. The final gain on this divestiture was $53.1 million. A portion of the transaction was structured to qualify as a like-kind exchange under Section 1031 of the Internal Revenue Code. Assets Held for Sale Assets are classified as held for sale when the Company commits to a plan to sell the assets and there is reasonable certainty the sale will take place within one year. Upon classification as held for sale, long-lived assets are no longer depreciated or depleted, and a measurement for impairment is performed to identify and expense any excess of carrying value over fair value less costs to sell. Subsequent changes to estimated fair value less the cost to sell will impact the measurement of assets held for sale for which fair value is determined to be less than the carrying value of the assets. In July 2011, the Company entered into agreements with Endeavour to divest of our Marcellus shale assets and related pipeline facilities located in Pennsylvania for $80.0 million net to the Company's interest. Subsequently, Endeavour failed to consummate the transaction after giving notice of its intent to terminate the agreement. The Company has disputed Endeavour's right to take these actions and is currently pursuing legal remedies including specific performance or damages from Endeavour. Due to the uncertainty surrounding the transaction, it was determined that these assets do not continue to meet the specific criteria required for presentation as assets held for sale. As a result the Company has reclassified these assets previously classified as held for sale to assets held and used. The Company measured the assets at the lower of the assets carrying amount before the assets were classified as held for sale, adjusted for any depreciation and depletion expense that would have been recognized had the assets been continuously classified as held and used, or the assets fair value at the subsequent date that the assets no longer met the criteria for assets held for sale. As a result of this measurement, the Company recognized $14.7 million of DD&A expense and a $27.5 million write-down to proved and unproved oil and gas properties. This write-down is included in gain on divestiture activity in the accompanying statements of operations. The Company determined that none of the divestitures addressed above qualified for discontinued operations accounting under financial statement presentation authoritative accounting guidance.

Note 3 – Divestitures and Assets Held for Sale

Eagle Ford Shale Divestiture

In August 2011, the Company divested of certain operated Eagle Ford shale assets located in its South Texas & Gulf Coast region. This divestiture was comprised of the Company's entire operated acreage in LaSalle County, Texas, as well as an immaterial adjacent block of its operated acreage in Dimmit County, Texas. Total divestiture proceeds were $230.8 million. The estimated gain on this divestiture was $194.6 million. The final divestiture proceeds are subject to normal post-closing adjustments and are expected to be finalized during the first quarter of 2012.

Mid-Continent Divestiture

In June 2011, the Company divested of certain non-strategic assets located in its Mid-Continent region. Total divestiture proceeds were $35.8 million. The estimated gain on this divestiture was $28.5 million. The final divestiture proceeds are subject to normal post-closing adjustments and are expected to be finalized during the first quarter of 2012.

Rocky Mountain Divestiture

In January 2011, the Company divested of certain non-strategic assets located in its Rocky Mountain region. Total divestiture proceeds were $45.5 million. The final gain on this divestiture was $27.2 million.

Permian Divestiture

In December 2010, the Company completed the divestiture of certain non-strategic assets located in its Permian region. Total divestiture proceeds were $54.7 million. The final gain on this divestiture was $18.4 million.

Legacy Divestiture

In February 2010, the Company completed the divestiture of certain non-strategic assets located in its Rocky Mountain region. Total divestiture proceeds were $125.3 million. The final gain on this divestiture was $66.7 million. A portion of the transaction was structured to qualify as a like-kind exchange under Section 1031 of the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”).

Sequel Divestiture

In March 2010, the Company completed the divestiture of certain non-strategic assets located in its Rocky Mountain region. Total divestiture proceeds were $129.1 million. The final gain on this divestiture was $53.1 million. A portion of the transaction was structured to qualify as a like-kind exchange under Section 1031 of the Internal Revenue Code.

Assets Held for Sale

Assets are classified as held for sale when the Company commits to a plan to sell the assets and there is reasonable certainty the sale will take place within one year. Upon classification as held for sale, long-lived assets are no longer depreciated or depleted, and a measurement for impairment is performed to identify and expense any excess of carrying value over fair value less costs to sell. Subsequent changes to estimated fair value less the cost to sell will impact the measurement of assets held for sale for which fair value is determined to be less than the carrying value of the assets.

In July 2011, the Company entered into agreements with Endeavour to divest of our Marcellus shale assets and related pipeline facilities located in Pennsylvania for $80.0 million net to the Company's interest. Subsequently, Endeavour failed to consummate the transaction after giving notice of its intent to terminate the agreement. The Company has disputed Endeavour's right to take these actions and is currently pursuing legal remedies including specific performance or damages from Endeavour. Due to the uncertainty surrounding the transaction, it was determined that these assets do not continue to meet the specific criteria required for presentation as assets held for sale. As a result the Company has reclassified these assets previously classified as held for sale to assets held and used. The Company measured the assets at the lower of the assets carrying amount before the assets were classified as held for sale, adjusted for any depreciation and depletion expense that would have been recognized had the assets been continuously classified as held and used, or the assets fair value at the subsequent date that the assets no longer met the criteria for assets held for sale. As a result of this measurement, the Company recognized $14.7 million of DD&A expense and a $27.5 million write-down to proved and unproved oil and gas properties. This write-down is included in gain on divestiture activity in the accompanying statements of operations.

The Company determined that none of the divestitures addressed above qualified for discontinued operations accounting under financial statement presentation authoritative accounting guidance.