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Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Mar. 31, 2016 | Feb. 01, 2016 | Nov. 24, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Asset retirement obligation capitalized | $ 10,971 | $ 8,800 | $ 9,295 |  |  |
Mammoth Energy Partners LP |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Fair value of equity investment |  |  | 143,500 |  |  |
Strike Force Midstream LLC |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Fair value of equity investment |  |  | $ 22,500 |  |  |
Level 3 |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Asset retirement obligation capitalized | $ 11,000 |  |  |  |  |
Level 3 | Mammoth Energy Partners LP |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Fair value of equity investment |  |  |  |  |  | $ 143,500
Level 3 | Investment in Grizzly Oil Sands ULC |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Fair value of equity investment |  |  |  | $ 39,100 |  |
Level 3 | Strike Force Midstream LLC |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Fair value of equity investment |  |  |  |  | $ 22,500 |

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