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Equity Investments (Investments Accounted For By The Equity Method) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015 | Dec. 31, 2015
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Equity investments | $ 253,047 |  | $ 253,047 |  | $ 242,393
Loss (income) from equity method investments | $ 836 | $ 15,120 | $ 31,573 | $ (4,855) |
Investment in Tatex Thailand II, LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 23.50% |  | 23.50% |  |
Loss (income) from equity method investments | $ 0 | 0 | $ (159) | 0 |
Investment in Tatex Thailand III, LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 17.90% |  | 17.90% |  |
Equity investments | $ 0 |  | $ 0 |  |
Loss (income) from equity method investments | $ 0 | 189 | $ 0 | 189 |
Investment in Grizzly Oil Sands ULC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 24.9999% |  | 24.9999% |  |
Equity investments | $ 49,556 |  | $ 49,556 |  | 50,645
Loss (income) from equity method investments | $ 763 | 8,494 | $ 24,448 | 12,636 |
Investment in Timber Wolf Terminals LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 50.00% |  | 50.00% |  |
Equity investments | $ 996 |  | $ 996 |  | 999
Loss (income) from equity method investments | $ 1 | 7 | $ 4 | 13 |
Investment in Windsor Midstream LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 22.50% |  | 22.50% |  |
Equity investments | $ 26,147 |  | $ 26,147 |  | 27,955
Loss (income) from equity method investments | $ (2,881) | 881 | $ (3,048) | (17,906) |
Investment in Stingray Cementing LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 50.00% |  | 50.00% |  |
Equity investments | $ 2,359 |  | $ 2,359 |  | 2,487
Loss (income) from equity method investments | $ 78 | 105 | $ 108 | 172 |
Investment in Blackhawk Midstream LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 48.50% |  | 48.50% |  |
Equity investments | $ 0 |  | $ 0 |  | 0
Loss (income) from equity method investments | $ 0 | 0 | $ 0 | (7,217) |
Investment in Stingray Energy Services LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 50.00% |  | 50.00% |  |
Equity investments | $ 4,981 |  | $ 4,981 |  | 5,908
Loss (income) from equity method investments | $ 139 | 311 | $ 641 | 321 |
Investment in Sturgeon Acquisitions LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 25.00% |  | 25.00% |  |
Equity investments | $ 22,258 |  | $ 22,258 |  | 22,769
Loss (income) from equity method investments | $ 134 | (491) | $ 511 | (1,059) |
Investment in Mammoth Energy Partners LP |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 30.50% |  | 30.50% |  |
Equity investments | $ 121,309 |  | $ 121,309 |  | 131,630
Loss (income) from equity method investments | $ 2,543 | 5,624 | $ 9,009 | 7,996 |
Investment in Strike Force Midstream LLC |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Approximate ownership % | 25.00% |  | 25.00% |  |
Equity investments | $ 25,441 |  | $ 25,441 |  | $ 0
Loss (income) from equity method investments | $ 59 | $ 0 | $ 59 | $ 0 |

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