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MARKETABLE SECURITIES - Activity in Investments (Details) - USD ($) $ in Thousands | 6 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024
Investments rollforward |  |
Opening balance | $ 1,617 |
Additions/transfers during period | 8,445 |
Disposals/transfers during period | (548) |
Unrealized gain on securities held | 6,453 |
Ending balance | 15,967 |
Marketable securities |  |
Investments rollforward |  |
Opening balance | 1,206 | $ 1,743
Additions/transfers during period | 7,463 |
Disposals/transfers during period | (168) | (82)
Unrealized gain on securities held | 5,386 | 284
Ending balance | 13,887 | $ 1,945
Warrants |  |
Investments rollforward |  |
Opening balance | 411 |
Additions/transfers during period | 982 |
Disposals/transfers during period | (380) |
Unrealized gain on securities held | 1,067 |
Ending balance | $ 2,080 |

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