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INVESTMENTS (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2018 | Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Investments rollforward |  |  |  |
Opening balance |  | $ 7,971 | $ 8,543 | $ 8,543
Disposals during the period |  | (3,397) |  | (2,163)
Other Comprehensive Income (Loss) (pre -tax) |  |  |  | 1,334
Statement of Operations (Loss) Income |  | (2,001) |  | 257
Fair Value end of the year | $ 2,573 | 2,573 |  | 7,971
Fair value of warrants |  |  |  |
Unrealized gain on available-for-sale securities, net of taxes (note 2) |  | (1,137) |  |
Cost of purchase of marketable equity securities | 1,400 |  |  | 3,300
Unrealized (loss) gain on derivatives (note 2) |  | (864) | 1,791 |
Proceeds from sale of investments |  | 2,663 |  |
Unrealized loss on available-for-sale securities |  | 900 |  |
Unrealized gain on available-for-sale securities |  |  | 1,800 |
Marketable equity securities |  |  |  |
Investments rollforward |  |  |  |
Opening balance |  | 6,404 | 6,749 | 6,749
Disposals during the period |  | (3,397) |  | (2,163)
Other Comprehensive Income (Loss) (pre -tax) |  |  |  | 1,334
Statement of Operations (Loss) Income |  | (1,137) |  | 484
Fair Value end of the year | 1,870 | 1,870 |  | 6,404
Warrants |  |  |  |
Investments rollforward |  |  |  |
Opening balance |  | 1,567 | $ 1,794 | 1,794
Statement of Operations (Loss) Income |  | (864) |  | (227)
Fair Value end of the year | $ 703 | $ 703 |  | $ 1,567

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