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Condensed Consolidated Financial Statements Detail - Equity Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Equity Securities |  |  |  |  |
Long-term equity securities |  |  |  |  | $ 1,693
Gain (loss) recognized due to change in fair value of investment |  |  | $ 617 | $ (150) |
Rezolute |  |  |  |  |
Equity Securities |  |  |  |  |
Long-term equity securities | $ 2,300 |  | 2,300 |  | $ 1,700
Gain (loss) recognized due to change in fair value of investment | $ 1,300 | $ 100 | $ 600 | $ (200) |

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