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Fair Value Measurements (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Dec. 31, 2014
Liabilities: |  |  |
Asset retirement obligation capitalized | $ 5,736 | $ 5,713 |
Mammoth Energy Partners LP [Member] |  |  |
Liabilities: |  |  |
Equity investment |  |  | $ 143,500
Level 1 [Member] |  |  |
Assets: |  |  |
Derivative Instruments | 167,271 |  |
Liabilities: |  |  |
Derivative Instruments | 5,559 |  |
Level 2 [Member] |  |  |
Assets: |  |  |
Derivative Instruments | 0 |  |
Liabilities: |  |  |
Derivative Instruments | 0 |  |
Level 3 [Member] |  |  |
Assets: |  |  |
Derivative Instruments | 0 |  |
Liabilities: |  |  |
Derivative Instruments | 0 |  |
Asset retirement obligation capitalized | $ 5,700 |  |
Level 3 [Member] | Mammoth Energy Partners LP [Member] |  |  |
Liabilities: |  |  |
Equity investment |  |  | $ 143,500

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