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Collaboration and Other Agreements, Zai Lab (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Nov. 30, 2018 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $ 15,794 | $ 20,798 | $ 18,834 | $ 4,695 | $ 152,359 | $ 1,663 | $ 1,666 | $ 2,055 | $ 60,121 | $ 157,742 | $ 91,880
Deferred revenue |  | 40,722 |  |  |  | $ 27,318 |  |  |  | 40,722 | $ 27,318 |
Zai Lab Agreement | Zai Lab |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Non-refundable upfront payment | $ 25,000 |  |  |  |  |  |  |  |  |  |  |
Tax withholding | $ 2,500 |  |  |  |  |  |  |  |  |  |  |
Potential development and regulatory milestone payments |  | 140,000 |  |  |  |  |  |  |  | 140,000 |  |
Revenues |  |  |  |  |  |  |  |  |  | 1,300 |  |
Deferred revenue |  | 21,100 |  |  |  |  |  |  |  | 21,100 |  |
Deferred revenue, current |  | $ 16,100 |  |  |  |  |  |  |  | $ 16,100 |  |

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