Supplemental Information on Oil and Gas Exploration and Production Activities (Unaudited) - Costs Incurred In Oil and Gas Property Acquisition and Development Activities (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] | |||
| Acquisition | $ 1,951,281 | $ 152,887 | $ 810,755 |
| Development of proved undeveloped properties | 994,237 | 423,998 | 642,811 |
| Exploratory | 0 | 0 | 0 |
| Recompletions | 14,289 | 16,386 | 13,894 |
| Capitalized asset retirement obligation | 42,270 | 10,971 | 8,800 |
| Total | 3,002,077 | 604,242 | 1,476,260 |
| Investment in Grizzly Oil Sands ULC | |||
| Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] | |||
| Acquisition | 503 | 357 | 396 |
| Development of proved undeveloped properties | 0 | 0 | 47 |
| Exploratory | 0 | 0 | 0 |
| Capitalized asset retirement obligation | (524) | 784 | 282 |
| Total | $ (21) | $ 1,141 | $ 725 |
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- Definition Costs incurred for the recompletion of oil and gas wells No definition available.
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- Definition Total costs incurred in oil and gas properties acquisition and development activities No definition available.
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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 Amount of asset retirement obligations (ARO) costs incurred (whether capitalized or charged to expense) during the period. 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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Details
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