Oil and Gas Producing Activities - Schedule of Information Regarding Results of Operations for Oil and Gas Producing Activities (Detail) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Extractive Industries [Abstract] | |||
| Revenues | $ 105,349,000 | $ 90,302,000 | $ 131,336,000 |
| Production costs | (26,546,000) | (27,467,000) | (40,057,000) |
| Exploration expense | (3,657,000) | (3,923,000) | (4,439,000) |
| Depletion | (70,521,000) | (79,044,000) | (109,319,000) |
| Impairment of oil and gas properties | 0 | 0 | (220,197,000) |
| Income tax benefit (expense) | (1,641,000) | 7,144,000 | 86,120,000 |
| Results of operations | $ 2,984,000 | $ (12,988,000) | $ (156,556,000) |
| X | ||||||||||
- Definition Results of operations income tax expense (benefit). No definition available.
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| X | ||||||||||
- Definition Exploration expenses (including prospecting) related to oil and gas producing entities and would be included in operating expenses of that entity. Costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: (i) Costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. (ii) Costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, and the maintenance of land and lease records. (iii) Dry hole contributions and bottom hole contributions. (iv) Costs of drilling and equipping exploratory wells. (v) Costs of drilling exploratory-type stratigraphic test wells. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Depreciation, depletion and amortization, and valuation provisions (impairments) related to oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The results of operations for oil and gas producing activities, excluding corporate overhead and interest costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Production (lifting) costs from oil and gas producing activities, including but not limited to lease operating expense, production and ad valorem taxes, and transportation expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total revenues from oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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