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Fair Value Measurements - Contingent Consideration (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 | Dec. 31, 2019 | Feb. 25, 2019
Fair Value Measurements |  |  |
Contingent consideration under royalty purchase agreements |  | $ 75 |
Bioasis Technologies Inc | Royalty Purchase Agreement |  |  |
Fair Value Measurements |  |  |
Changes in estimated fair value of contingent consideration |  | 0 |
Contingent consideration under royalty purchase agreements |  | 100 | $ 100
Contingent consideration paid |  | $ 0 |
Aronora | Royalty Purchase Agreement |  |  |
Fair Value Measurements |  |  |
Contingent consideration paid | $ 3,000 |  |

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