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Supplemental Oil And Gas Disclosures (Tables) | 12 Months Ended
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Dec. 31, 2011
Supplemental Oil And Gas Disclosures [Abstract] |
Capitalized Costs |
|  |  | September 30, |  |  |  | September 30, |
|  | December 31, |
|  | 2011 |  |  | 2010 |
|  | (In thousands) |
Proved oil and gas properties |  | $ | 1,152,532 |  |  | $ | 479,657 |
Less: Accumulated depreciation, depletion, amortization and impairment |  |  | (174,948 | ) |  |  | (98,821 | )
Proved oil and gas properties, net |  |  | 977,584 |  |  |  | 380,836 |
Unproved oil and gas properties |  |  | 82,825 |  |  |  | 101,311 |
Total oil and gas properties, net |  | $ | 1,060,409 |  |  | $ | 482,147 |
Costs Incurred In Oil And Natural Gas Property Acquisition, Exploration And Development Activities |
|  |  | September 30, |  |  |  | September 30, |  |  |  | September 30, |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (In thousands) |
Acquisition costs: |  |  |  |  |  |  |  |  |  |  |  |
Proved oil and gas properties |  | $ | 3,356 |  |  | $ | 20,259 |  |  | $ | 35,134 |
Unproved oil and gas properties |  |  | 15,197 |  |  |  | 81,624 |  |  |  | 13,917 |
Exploration costs |  |  | 1,685 |  |  |  | 297 |  |  |  | 1,019 |
Development costs |  |  | 618,737 |  |  |  | 243,758 |  |  |  | 38,526 |
Asset retirement costs |  |  | 5,055 |  |  |  | 968 |  |  |  | 1,314 |
Total costs incurred |  | $ | 644,030 |  |  | $ | 346,906 |  |  | $ | 89,910 |
Results Of Operations For Oil And Natural Gas Producing Activities |
|  |  | September 30, |  |  |  | September 30, |  |  |  | September 30, |
|  | December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (In thousands) |
Revenues |  | $ | 330,422 |  |  | $ | 128,927 |  |  | $ | 37,755 |
Production costs |  |  | 67,937 |  |  |  | 28,350 |  |  |  | 12,501 |
Depreciation, depletion and amortization |  |  | 74,101 |  |  |  | 37,583 |  |  |  | 16,592 |
Exploration costs |  |  | 1,685 |  |  |  | 297 |  |  |  | 1,019 |
Rig termination(1) |  |  | — |  |  |  | — |  |  |  | 3,000 |
Impairment of oil and gas properties |  |  | 3,610 |  |  |  | 11,967 |  |  |  | 6,233 |
Loss (gain) on sale of properties |  |  | 207 |  |  |  | — |  |  |  | (1,455 | )
Income tax expenses |  |  | 64,009 |  |  |  | 17,756 |  |  |  | — |
Results of operations for oil and gas producing activities |  | $ | 118,873 |  |  | $ | 32,974 |  |  | $ | (135 | )
(1) | During the first quarter of 2009, we paid a total of $3.0 million in rig termination expenses in connection with early termination of two drilling rig contracts entered into in 2008. We did not have any rig termination expenses during the years ended December 31, 2011 and 2010.

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