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EQUITY INVESMENTS (Narrative) (Details) $ / shares in Units, a in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2019 USD ($) shares | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) a $ / shares shares | Jun. 30, 2018 USD ($) | May 31, 2018 | May 01, 2018
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Loss (income) from equity method investments, net | $ 125,582,000 | $ (8,888,000) | $ 121,309,000 | $ (22,424,000) |  |
Distributions from equity method investments |  |  | 1,945,000 | 1,196,000 |  |
Mammoth Energy Services LP |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Equity method investment, impairment |  |  | 125,400,000 |  |  |
Distributions from equity method investments |  |  | $ 2,500,000 |  |  |
Equity method investment, ownership interest (in shares) | shares | 9,829,548 |  | 9,829,548 |  |  |
Share dividend (in usd per share) | $ / shares |  |  | $ 0.125 |  |  |
Approximate fair value, quoted market price | $ 67,700,000 |  | $ 67,700,000 |  |  |
Tatex Thailand II, LLC |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Loss (income) from equity method investments, net | $ (1,945,000) | (63,000) | $ (2,085,000) | (104,000) |  |
Equity method investment, ownership interest, percent | 23.50% |  | 23.50% |  |  |
Grizzly Oil Sands ULC |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Gas and oil area, reserve (in acres) | a |  |  | 830 |  |  |
Loss (income) from equity method investments, net | $ (54,000) | 228,000 | $ 339,000 | 558,000 |  |
Equity method investment, impairment |  |  | 0 | 0 |  |
Equity method investment, amount of cash calls, based on proportionate ownership interest |  |  | 400,000 |  |  |
Equity method investments, increase (decrease) due to foreign currency translation adjustment | $ 3,500,000 | (3,400,000) | $ 7,300,000 | (8,700,000) |  |
Equity method investment, ownership interest, percent | 24.9999% |  | 24.9999% |  |  |
Windsor Midstream LLC |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Loss (income) from equity method investments, net | $ 0 | (9,000) | $ 0 | (9,000) |  |
Equity method investment, ownership interest, percent | 22.50% |  | 22.50% |  |  |
Distributions from equity method investments |  |  | $ 0 |  |  |
Mammoth Energy Services LP |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Equity method investments, increase (decrease) due to foreign currency translation adjustment | $ 100,000 | (100,000) | 200,000 | (300,000) |  |
Strike Force Midstream LLC |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Loss (income) from equity method investments, net | $ 0 | $ (336,000) | $ 0 | $ (693,000) |  |
Equity method investment, ownership interest, percent | 0.00% |  | 0.00% |  |  | 25.00%
Phu Horm Field | Apico Llc |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Gas and oil area, reserve (in acres) | a |  |  | 108 |  |  |
Apico Llc | Tatex Thailand II, LLC |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Ownership percentage | 8.50% |  | 8.50% |  |  |
Apico Llc | Tatex Thailand II, LLC |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Loss (income) from equity method investments, net |  |  | $ (1,900,000) |  |  |
Investee | Mammoth Energy Services LP |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Equity method investment, ownership interest, percent | 21.80% |  | 21.80% |  |  |
Investee | Strike Force Midstream LLC |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |
Equity method investment, ownership interest, percent |  |  |  |  | 25.00% |

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