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Condensed Consolidated Financial Statements Details - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018
Long-term Equity Securities [Line Items] |  |  |  |  |  |
Long-term equity securities | $ 873 |  | $ 873 |  | $ 392 | [1]
Gain (loss) recognized due to change in fair value of investment |  |  | 481 | $ (608) |  |
Rezolute [Member] |  |  |  |  |  |
Long-term Equity Securities [Line Items] |  |  |  |  |  |
Long-term equity securities | 900 |  | 900 |  | $ 400 |
Gain (loss) recognized due to change in fair value of investment | $ (300) | $ (200) | $ 500 | $ (600) |  |
[1] | The consolidated balance sheet as of December 31, 2018 has been derived from the audited consolidated financial statements as of that date included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018.

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