Property and Equipment (Narrative) (Details) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
Dec. 31, 2016 |
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| Property, Plant and Equipment [Line Items] | |||||
| Impairment of oil and natural gas properties | $ 0 | $ 212,194,000 | $ 0 | $ 601,806,000 | |
| Cumulative capitalization of general and administrative costs incurred and capitalized to the full cost pool | 155,500,000 | 155,500,000 | |||
| Capitalized general and administrative costs | 8,900,000 | $ 7,200,000 | 25,600,000 | $ 22,200,000 | |
| Capitalized costs of oil and natural gas properties excluded from amortization | $ 2,956,732,000 | $ 2,956,732,000 | $ 1,580,305,000 | ||
| Non-producing leases, extension term | 5 years | ||||
| Minimum | |||||
| Property, Plant and Equipment [Line Items] | |||||
| Expected number of years amortization will commence | 3 years | ||||
| Maximum | |||||
| Property, Plant and Equipment [Line Items] | |||||
| Expected number of years amortization will commence | 5 years | ||||
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- Definition Anticipated Timing of Inclusion of Costs in Amortization Calculation, Period No definition available.
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- Definition General and administrative costs capitalized to the full cost pool. No definition available.
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- Definition Cumulative capitalization of general and administrative costs incurred and capitalized to the full cost pool. No definition available.
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- Definition The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs. 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 Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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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