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INVESTMENTS - Activity in Investments (Details) - USD ($) $ in Thousands | 6 Months Ended
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Jun. 30, 2021 | Jun. 30, 2020
Investments rollforward |  |
Additions/transfers during the period | $ 1,777 |
Fair Value end of the period | 1,777 |
Marketable equity securities |  |
Investments rollforward |  |
Opening balance |  | $ 1,885
Additions/transfers during the period | 1,616 |
Net gain (loss) on securities sold |  | (619)
Disposals/transfers during period |  | (1,266)
Fair Value end of the period | 1,616 | $ 0
Warrants |  |
Investments rollforward |  |
Additions/transfers during the period | 161 |
Fair Value end of the period | $ 161 |

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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740 + Details
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