Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Deferred tax asset | ||
| Federal net operating loss carryforward | $ 97,437 | $ 135,711 |
| Statutory depletion carryforward | 5,381 | 8,843 |
| Alternative minimum tax credit carryforward | 52 | 104 |
| Asset retirement obligations | 572 | 1,181 |
| Derivatives | 6,186 | 6,456 |
| Unvested RSU equity awards | 1,749 | 2,092 |
| Other | 2,401 | 4,376 |
| Deferred tax asset before valuation allowance | 113,778 | 158,763 |
| Deferred tax liability | ||
| Oil and natural gas properties | 54,264 | 18,661 |
| Total deferred tax liability | 54,264 | 18,661 |
| Net deferred tax asset before valuation allowance | 59,514 | 140,102 |
| Less: Valuation allowance | (60,919) | (140,192) |
| Net deferred tax liabilities | (1,405) | $ (90) |
| Reduction i deferred tax assets | 40,611 | |
| Unrealized excess tax benefits related to stock based compensation | $ 9,288 |
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- Definition Deferred Tax Assets, Statutory Depletion Carryforward No definition available.
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- Definition Deferred TaxAssets Liabilities Net Before Valuation Allowance No definition available.
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- Definition Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Increase (Decrease) In Deferred Tax Asset, Net No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from derivative instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from asset retirement obligations. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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