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Collaboration and Other Agreements, Provention (Details) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
May 31, 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
Provention Bio, Inc. (Provention) |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Transaction price | $ 6,100 |  |  |  |  |  |  |  |  |  |  |
Stock warrants (in shares) | 2,432,688 |  |  |  |  |  |  |  |  |  |  |
Fair Value Adjustment of Warrants |  |  |  |  |  |  |  |  |  | $ 4,200 |  |
Provention License Agreement | Provention PRV3279 | Provention Bio, Inc. (Provention) |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Consideration received common stock warrant exercise price (in usd per share) | $ 2.50 |  |  |  |  |  |  |  |  |  |  |
Potential development and regulatory milestone payments | $ 65,000 |  |  |  |  |  |  |  |  |  |  |
Potential commercial milestone payments | $ 225,000 |  |  |  |  |  |  |  |  |  |  |
Asset Purchase Agreement | Provention PRV031 | Provention Bio, Inc. (Provention) |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Consideration received common stock warrant exercise price (in usd per share) | $ 2.50 |  |  |  |  |  |  |  |  |  |  |
Potential development and regulatory milestone payments | $ 170,000 |  |  |  |  |  |  |  |  |  |  |
Potential commercial milestone payments | 225,000 |  |  |  |  |  |  |  |  |  |  |
Potential milestone payment to third parties for intellectual property under agreement | 1,300 |  |  |  |  |  |  |  |  |  |  |
Revenues From License Agreements | Provention Bio, Inc. (Provention) |  |  |  |  |  |  |  |  |  |  |  |
Collaboration and Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues | $ 6,100 |  |  |  |  |  |  |  |  |  |  |

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