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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 | Oct. 31, 2017 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Feb. 29, 2020
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  | $ 25,192 | $ 18,741 | $ 10,593 | $ 9,662 | $ 15,794 | $ 20,798 | $ 18,834 | $ 4,695 | $ 64,188 | $ 60,121 | $ 157,742 |
Deferred revenue |  |  |  |  |  |  | $ 40,722 |  |  |  |  | 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 |  |  |  |  |  |  |  |  |  |  | 16,100 | $ 1,300 |  |
Deferred revenue |  |  | $ 5,000 |  |  |  |  |  |  |  | 5,000 |  |  |
Zai Lab Agreement | Zai Lab | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Entitled milestone payments |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,000
Zai Lab Agreement, Margetuximab | Zai Lab | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential proceeds from royalties percent |  | 20.00% |  |  |  |  |  |  |  |  |  |  |  |
Zai Lab Agreement, TRIDENT molecule | Zai Lab |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential proceeds from royalties percent |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |
Zai Lab Clinical Supply Agreements | Zai Lab |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  | $ 2,200 |  |  |

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