Property and Equipment (Schedule of Property and Equipment) (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Property, Plant and Equipment [Abstract] | ||
| Oil and natural gas properties | $ 9,470,697 | $ 9,169,156 |
| Office furniture and fixtures | 40,236 | 37,369 |
| Building | 44,592 | 44,565 |
| Land | 4,820 | 4,820 |
| Total property and equipment | 9,560,345 | 9,255,910 |
| Accumulated depletion, depreciation, amortization and impairment | (4,264,647) | (4,153,733) |
| Property and equipment, net | $ 5,295,698 | $ 5,102,177 |
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- Definition Accumulated Deprecation, Depletion, Amortization and Impairment, Property, Plant, and Equipment No definition available.
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- Definition Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before accumulated depletion of real estate held for productive use, excluding land held for sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Oil and gas properties, gross, carried under the full cost method. No definition available.
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- References No definition available.
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- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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