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INVESTMENTS (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Investments rollforward |  |  |
Opening balance | $ 3,131 | $ 7,971 |
Additions/transfers during the period | 2,314 | 2,083 |
Net gain (loss) on securities sold | 4,523 | (767) |
Disposals/transfers during period | (8,819) | (3,599) |
Unrealized gains (loss) on securities held | 736 | (2,557) |
Fair Value end of the period | 1,885 | 3,131 | $ 7,971
Proceeds from sale of investments | 6,769 | 2,895 | 2,155
Cost of purchase of marketable equity securities | 1,300 | 2,900 |
Other-than-temporary impairment on marketable equity securities |  |  | 356
Marketable equity securities |  |  |
Investments rollforward |  |  |
Opening balance | 2,718 | 6,404 |
Additions/transfers during the period | 2,314 | 1,882 |
Net gain (loss) on securities sold | 3,396 | (767) |
Disposals/transfers during period | (7,279) | (2,895) |
Unrealized gains (loss) on securities held | 736 | (1,906) |
Fair Value end of the period | 1,885 | 2,718 | 6,404
Proceeds from sale of investments | 6,800 | 2,900 | 2,200
Warrants |  |  |
Investments rollforward |  |  |
Opening balance | 413 | 1,567 |
Additions/transfers during the period |  | 201 |
Net gain (loss) on securities sold | 1,127 |  |
Disposals/transfers during period | $ (1,540) | (704) |
Unrealized gains (loss) on securities held |  | (651) |
Fair Value end of the period |  | $ 413 | $ 1,567

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