Supplemental Information on Oil and Gas Exploration and Production Activities (Unaudited) - Results of Operations for Producing Activities (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Results of Operations for Oil and Gas Producing Activities [Line Items] | |||
| Revenues | $ 385,910,000 | $ 708,990,000 | $ 670,762,000 |
| Production costs | (248,125,000) | (222,805,000) | (140,664,000) |
| Depletion | (243,098,000) | (335,288,000) | (263,946,000) |
| Impairment | (715,495,000) | (1,440,418,000) | 0 |
| Results of operations, before income taxes | (820,808,000) | (1,289,521,000) | 266,152,000 |
| Income Tax Expense (Benefit), Continuing Operations [Abstract] | |||
| Current | 0 | 0 | 0 |
| Deferred | 0 | (220,201,000) | 96,061,000 |
| Income tax expense | 0 | (220,201,000) | 96,061,000 |
| Results of operations from producing activities | (820,808,000) | (1,069,320,000) | 170,091,000 |
| Depletion per Mcf of gas equivalent (Mcfe) | 0.92 | 1.68 | 3.01 |
| Investment in Grizzly Oil Sands ULC | |||
| Results of Operations for Oil and Gas Producing Activities [Line Items] | |||
| Revenues | 0 | 1,436,000 | 5,449,000 |
| Production costs | (13,000) | (1,549,000) | (10,113,000) |
| Depletion | 0 | (625,000) | (1,195,000) |
| Results of operations, before income taxes | (13,000) | (738,000) | (5,859,000) |
| Income Tax Expense (Benefit), Continuing Operations [Abstract] | |||
| Income tax expense | 0 | 0 | 0 |
| Results of operations from producing activities | $ (13,000) | $ (738,000) | $ (5,859,000) |
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- Definition Depletion per MCF of Gas Equivalent No definition available.
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- Definition Results of operations income tax expense current No definition available.
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- Definition Results of operations income tax expense deferred No definition available.
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- Definition [Line Items] for Results of Operations for Oil and Gas Producing Activities [Table] 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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- References No definition available.
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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 Income before income taxes for oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Income tax expense for 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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- Details
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