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INVESTMENTS (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 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 |  |  |  |  |
Net gains (loss) on securities sold |  | (734) |  |  |  |
Disposals during the period |  | (2,663) |  |  |  |
Unrealized gains (loss) on securities held | 827 | (2,001) |  |  |  |
Fair Value end of the period | 4,222 | 2,573 | 3,131 |  |  |
Cumulative effect of new accounting principle | 100 |  |  |  |  |
Proceeds from sale of investments |  | 2,663 |  |  |  |
Cost of purchase of marketable equity securities | 3,100 |  | 2,900 |  |  |
Price per unit |  |  |  | $ 1.55 |  |
Flow Through Common Shares |  |  |  |  |  |
Investments rollforward |  |  |  |  |  |
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 |  |  |  |  |
Net gains (loss) on securities sold |  | (734) |  |  |  |
Disposals during the period |  | (2,663) |  |  |  |
Unrealized gains (loss) on securities held | 605 | (1,137) |  |  |  |
Fair Value end of the period | 3,587 | 1,870 | 2,718 |  |  |
Warrants |  |  |  |  |  |
Investments rollforward |  |  |  |  |  |
Opening balance | 413 | 1,567 | 1,567 |  |  |
Unrealized gains (loss) on securities held | 222 | (864) |  |  |  |
Fair Value end of the period | $ 635 | $ 703 | $ 413 |  |  |

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