Oil and Gas Producing Activities - Schedule of Information Regarding Costs Incurred for Oil and Gas Property Acquisition, Development and Exploration Activities (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Extractive Industries [Abstract] | |||
| Unproved properties | $ 231 | $ 17 | $ 653 |
| Proved properties | 17,331 | ||
| Exploration costs | 3,657 | 3,923 | 4,439 |
| Development costs | 43,202 | 15,884 | 146,237 |
| Total costs incurred | $ 64,421 | $ 19,824 | $ 151,329 |
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- Definition Cost incurred, including capitalized costs and costs charged to expense, in acquisition of oil and gas properties. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have proved reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have unproved reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Development costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Exploration costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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