v3.19.3.a.u2

Collaboration Agreements - Alexion – 2014 Strategic Alliance in Rare Diseases (Details) | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 31, 2014 USD ($) candidate | Dec. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Sep. 30, 2018 USD ($) | Jun. 30, 2018 USD ($) | Mar. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Deferred revenue recognized |  |  |  |  |  |  |  |  |  | $ 51,987,000 |  |
Collaboration revenue |  | $ 14,055,000 | $ 17,046,000 | $ 13,083,000 | $ 16,025,000 | $ 35,421,000 | $ 41,757,000 | $ 28,851,000 | $ 29,039,000 | 60,209,000 | $ 135,068,000 | $ 205,825,000
Deferred revenue |  | 199,528,000 |  |  |  | 240,924,000 |  |  |  | 199,528,000 | 240,924,000 |
Collaboration revenue |  |  |  |  |  |  |  |  |  |  |  |
Research and Development Arrangement, Contract to Perform for Others [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Collaboration revenue |  |  |  |  |  |  |  |  |  | 42,803,000 | 76,519,000 | 146,953,000
2014 Alexion Agreements |  |  |  |  |  |  |  |  |  |  |  |
Research and Development Arrangement, Contract to Perform for Others [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront cash payments | $ 100,000,000 |  |  |  |  |  |  |  |  |  |  |
Proceeds from equity investment | $ 25,000,000 |  |  |  |  |  |  |  |  |  |  |
Number of product candidates | candidate | 10 |  |  |  |  |  |  |  |  |  |  |
Arrangement term | 10 years |  |  |  |  |  |  |  |  |  |  |
Deferred revenue recognized |  |  |  |  |  |  |  |  |  |  | 70,300,000 |
Deferred revenue |  | $ 0 |  |  |  | $ 0 |  |  |  | 0 | $ 0 |
2014 Alexion Agreements | Collaboration revenue |  |  |  |  |  |  |  |  |  |  |  |
Research and Development Arrangement, Contract to Perform for Others [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Collaboration revenue |  |  |  |  |  |  |  |  |  | $ 0 |  | $ 74,400,000

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