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EQUITY INVESMENTS (Investments Accounted for by the Equity Method) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | May 01, 2018 | Dec. 31, 2017 | Dec. 31, 2014
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Equity investments and investments in subsidiaries | $ 232,529 |  | $ 232,529 |  |  | $ 302,112 |
(Income) loss from equity method investments, net | $ (12,858) | $ 2,737 | $ (35,282) | $ 33,468 |  |  |
Investment in Tatex Thailand II, LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 23.50% |  | 23.50% |  |  |  |
Equity investments and investments in subsidiaries | $ 0 |  | $ 0 |  |  | 0 |
(Income) loss from equity method investments, net | $ (137) | (95) | $ (241) | (549) |  |  |
Investment in Grizzly Oil Sands ULC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 24.9999% |  | 24.9999% |  |  |  |
Equity investments and investments in subsidiaries | $ 53,381 |  | $ 53,381 |  |  | 57,641 |
(Income) loss from equity method investments, net | $ 275 | 296 | $ 833 | 869 |  |  |
Investment in Timber Wolf Terminals LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 50.00% |  | 50.00% |  |  |  |
Equity investments and investments in subsidiaries | $ 0 |  | $ 0 |  |  | 983 |
(Income) loss from equity method investments, net | $ 0 | 4 | $ 536 | 8 |  |  |
Investment in Windsor Midstream LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 22.50% |  | 22.50% |  |  |  |
Equity investments and investments in subsidiaries | $ 39 |  | $ 39 |  |  | 30 |
(Income) loss from equity method investments, net | $ 0 | (2) | $ (9) | 25,232 |  |  |
Investment in Stingray Cementing LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 0.00% |  | 0.00% |  |  |  |
Equity investments and investments in subsidiaries | $ 0 |  | $ 0 |  |  | 0 |
(Income) loss from equity method investments, net | $ 0 | 0 | $ 0 | 205 |  |  |
Investment in Stingray Energy Services LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 0.00% |  | 0.00% |  |  |  |
Equity investments and investments in subsidiaries | $ 0 |  | $ 0 |  |  | 0 |
(Income) loss from equity method investments, net | $ 0 | 0 | $ 0 | 282 |  |  |
Investment in Sturgeon Acquisitions LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 0.00% |  | 0.00% |  |  |  | 25.00%
Equity investments and investments in subsidiaries | $ 0 |  | $ 0 |  |  | 0 |
(Income) loss from equity method investments, net | $ 0 | 0 | $ 0 | (71) |  |  |
Investment in Mammoth Energy Services, Inc. |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 22.00% |  | 22.00% |  |  |  |
Equity investments and investments in subsidiaries | $ 179,109 |  | $ 179,109 |  |  | 165,715 |
(Income) loss from equity method investments, net | $ (12,996) | 2,407 | $ (35,708) | 4,907 |  |  |
Investment in Strike Force Midstream LLC |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Approximate ownership % | 0.00% |  | 0.00% |  | 25.00% |  |
Equity investments and investments in subsidiaries | $ 0 |  | $ 0 |  |  | $ 77,743 |
(Income) loss from equity method investments, net | $ 0 | $ 127 | $ (693) | $ 2,585 |  |  |

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