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Supplemental Information On Oil And Gas Exploration And Production Activities (Narrative) (Details) (USD $) | 12 Months Ended |  |  | 12 Months Ended
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Dec. 31, 2013 MBoe | Dec. 31, 2012 MBoe | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2011 | Dec. 31, 2013 Diamondback Energy LLC [Member] | Jun. 30, 2012 Diamondback Energy LLC [Member] | Dec. 31, 2013 Diamondback Energy, Inc [Member] | Dec. 31, 2012 Diamondback Energy, Inc [Member] MBoe | Dec. 31, 2011 Diamondback Energy, Inc [Member] | Dec. 31, 2013 Oil [Member] | Dec. 31, 2013 Natural Gas Liquids [Member]
Reserve Quantities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Ownership interest |  |  |  |  |  | 7.20% | 21.40% | 7.20% | 21.40% |  |  |
Future cash flows | $ 1,657,708,000 |  | $ 954,833,000 |  | $ 1,594,050,000 |  |  | $ 331,505,000 | $ 592,669,000 | $ 0 |  |
Future development and abandonment costs | (272,500,000) |  | (159,113,000) |  | (306,810,000) |  |  | (37,229,000) | (115,869,000) | 0 |  |
Future production costs | (274,428,000) |  | (147,024,000) |  | (295,383,000) |  |  | (58,096,000) | (165,553,000) | 0 |  |
Future production taxes | (78,647,000) |  | (89,175,000) |  | (124,739,000) |  |  | (22,925,000) | (30,122,000) | 0 |  |
Future income taxes | (172,691,000) |  | (114,867,000) |  | (229,649,000) |  |  | (48,547,000) | (71,669,000) | 0 |  |
Future net cash flows | 859,442,000 |  | 444,654,000 |  | 637,469,000 |  |  | 164,708,000 | 209,456,000 | 0 |  |
10% discount to reflect timing of cash flows | (280,976,000) |  | (96,013,000) |  | (260,788,000) |  |  | (94,462,000) | (130,871,000) | 0 |  |
Standardized measure of discounted future net cash flows | 578,466,000 |  | 348,641,000 |  | 376,681,000 |  |  | 70,246,000 | 78,585,000 | 0 |  |
Price per unit (usd per MMbls or MMcf) | 3.67 | 91.32 | 2.76 | 4.12 | 96.19 |  |  |  |  |  | 96.78 | 41.23
Increase (decrease) in reserve during the period | 27,805,000 | 6,675,000 | 6,675,000 |  |  |  |  |  | (12,564,000) |  |  |
Decrease in reserves relating to change in estimates |  | 442,000 | 442,000 |  |  |  |  |  |  |  |  |
Future development costs estimated to be spend in 2014 |  |  | 135,400,000 |  |  |  |  |  |  |  |  |
Future development costs estimated to be spend in 2015 |  |  | 68,700,000 |  |  |  |  |  |  |  |  |
Future development costs estimated to be spend in 2016 |  |  | $ 8,500,000 |  |  |  |  |  |  |  |  |

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- Definition The revenues derived from sales of oil or gas in each geographic area during the reporting period divided by the number of barrels of oil produced or thousands of cubic feet of gas produced. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 2 -Paragraph 3 -Subparagraph A + Details
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