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Income Taxes - Narrative (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Operating Loss Carryforwards [Line Items] |  |  |
Alternative minimum tax credits | $ 3,842,000 | $ 23,629,000 | $ 24,053,000
Foreign tax credit carryforwards | 2,074,000 | 2,074,000 | 2,074,000
Valuation allowance of deferred tax assets | 645,841,000 | 303,246,000 | 13,522,000
Change in deferred tax asset valuation | 343,944,000 | 278,637,000 | 0
Impairment of oil and gas properties | 715,495,000 | 1,440,418,000 | 0
Federal and state income taxes payable |  | $ 0 | 0
Diamondback |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Gain from sale of equity investment |  |  | 203,300,000
Change in deferred tax asset valuation |  |  | 79,400,000
Investment in Blackhawk Midstream LLC |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Gain from sale of equity investment |  |  | 83,700,000
Change in deferred tax asset valuation |  |  | $ 32,300,000
Federal |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Net operating loss carryforward | 463,100,000 |  |
State |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Net operating loss carryforward | $ 111,900,000 |  |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Alternative Minimum Tax -URI http://asc.fasb.org/extlink&oid=6504908 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32559-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32632-109319 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32621-109319 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign tax credit carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32559-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32621-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32632-109319 + Details
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