Supplemental Information on Oil and Natural Gas Properties (unaudited) (Capitalized Costs Relating to Oil and Natural Gas Activities) (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||
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Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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Evaluated Properties | |||||
Beginning of period balance | $ 2,335,223 | $ 2,754,353 | $ 2,335,223 | $ 2,077,985 | |
Capitalized G&A expenses | 11,982 | 12,222 | 10,529 | ||
Property acquisition costs | 144,358 | 216,561 | 26,726 | ||
Exploration costs | 239,453 | 38,612 | 81,320 | ||
Development costs | 279,424 | 151,735 | 138,663 | ||
End of period balance | 3,429,570 | 2,754,353 | 2,335,223 | ||
Unevaluated Properties | |||||
Beginning of period balance | 132,181 | 668,721 | 132,181 | 142,525 | |
Property acquisition costs | 590,308 | 548,673 | 5,520 | ||
Exploration costs | 6,374 | 8,631 | 4,576 | ||
Capitalized interest expenses | 33,783 | 19,857 | 10,459 | ||
Transfers to Evaluated Properties | (131,170) | (40,621) | (30,899) | ||
End of period balance | 1,168,016 | 668,721 | 132,181 | ||
Accumulated depreciation, depletion and amortization: | |||||
Beginning of period balance | 1,756,018 | 1,947,673 | 1,756,018 | 1,478,355 | |
Provision charged to expense | 115,897 | 71,330 | 69,228 | ||
Write-down of oil and natural gas properties | $ 61,012 | $ 34,776 | 0 | 95,788 | 208,435 |
Sale of mineral interests and equipment | 20,525 | 24,537 | 0 | ||
End of period balance | $ 2,084,095 | $ 1,947,673 | $ 1,756,018 |
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- Definition Capitalized Costs, Proved Properties, Capitalized General and Administration No definition available.
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- Definition Capitalized Costs, Proved Properties, Development Costs No definition available.
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- Definition Capitalized Costs, Proved Properties, Exploration Costs No definition available.
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- Definition Capitalized Costs, Proved Properties [Roll Forward] No definition available.
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- Definition Capitalized Costs, Provision Charged to Expense Relating to Oil and Gas Producing Activities No definition available.
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- Definition Capitalized Costs, Sale of Mineral Interests Relating to Oil and Gas Producing Activities No definition available.
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- Definition Capitalized Costs, Unproved Properties, Capitalized Interest No definition available.
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- Definition Capitalized Costs, Unproved Properties, Exploration No definition available.
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- Definition Capitalized Costs, Unproved Properties, Transfers to Evaluated No definition available.
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- Definition Unevaluated Properties (Excluded From Amortization): [Roll Forward] No definition available.
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- Definition Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Capitalized costs of unproved properties incurred for any combination mineral interests acquisitions and other costs not previously disclosed within this table. 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 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 A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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