v3.8.0.1

Fair Value Measurement (Details) $ in Thousands | 1 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2015 USD ($) bbl | Sep. 30, 2017 USD ($)
Reconciliation of changes in Level 3 financial liabilities measured at fair value on a recurring basis |  |
Beginning balance |  | $ 194,538
Accretion and change in fair value |  | 9,672
Ending balance |  | 204,210
Level 2 | 5.375% Senior Notes due 2024 |  |
Fair value measurement |  |
Debt instrument fair value |  | $ 676,000
Contribution Agreement | Contingent Consideration Period One |  |
Fair value measurement |  |
Contingent consideration | $ 125,000 |
Threshold number of barrels of water to trigger contingent consideration payment | bbl | 176,295,000 |
Contribution Agreement | Contingent Consideration Period Two |  |
Fair value measurement |  |
Contingent consideration | $ 125,000 |
Threshold number of barrels of water to trigger contingent consideration payment | bbl | 219,200,000 |

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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611 + Details
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