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INVESTMENTS (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | Mar. 29, 2019 | Dec. 20, 2018 | Dec. 19, 2017
Investments rollforward |  |  |  |  |  |  |  |
Opening balance |  |  | $ 3,131 | $ 7,971 | $ 7,971 |  |  |
Additions during the period |  |  | 264 | 1,211 |  |  |  |
Net gain (loss) on securities sold |  |  |  | (767) |  |  |  |
Disposals during period |  |  |  | (3,601) |  |  |  |
Unrealized gains (loss) on securities held | $ 900 | $ (500) | 1,752 | (2,502) |  |  |  |
Fair Value end of the period | 5,147 | 2,312 | 5,147 | 2,312 | 3,131 |  |  |
Fair value of warrants |  |  |  |  |  |  |  |
Proceeds from sale of investments |  |  |  | 3,667 |  |  |  |
Cost of purchase of marketable equity securities |  |  | 3,100 |  | 2,900 |  |  |
Price per unit |  |  |  |  |  | $ 1.55 |  |
Flow Through Common Shares |  |  |  |  |  |  |  |
Fair value of warrants |  |  |  |  |  |  |  |
Price per unit |  |  |  |  |  |  | $ 2.24 | $ 2.50
Marketable equity securities |  |  |  |  |  |  |  |
Investments rollforward |  |  |  |  |  |  |  |
Opening balance |  |  | 2,718 | 6,404 | 6,404 |  |  |
Additions during the period |  |  | 264 | 1,211 |  |  |  |
Net gain (loss) on securities sold |  |  |  | (767) |  |  |  |
Disposals during period |  |  |  | (2,899) |  |  |  |
Unrealized gains (loss) on securities held | 700 |  | 1,372 | (1,637) |  |  |  |
Fair Value end of the period | 4,354 | 2,312 | 4,354 | 2,312 | 2,718 |  |  |
Fair value of warrants |  |  |  |  |  |  |  |
Proceeds from sale of investments |  | $ 200 |  |  |  |  |  |
Warrants |  |  |  |  |  |  |  |
Investments rollforward |  |  |  |  |  |  |  |
Opening balance |  |  | 413 | 1,567 | 1,567 |  |  |
Disposals during period |  |  |  | (702) |  |  |  |
Unrealized gains (loss) on securities held |  |  | 380 | $ (865) |  |  |  |
Unrealized gains (loss) on warrants | 200 |  |  |  |  |  |  |
Fair Value end of the period | $ 793 |  | $ 793 |  | $ 413 |  |  |

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