v3.19.3.a.u2

Collaboration Agreements - Timing of Differences (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Jun. 30, 2019 | Jan. 01, 2019
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Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price | $ 249.5 |  |
PCVSAV Agreement |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price |  |  | $ 213.0
PCVSAV Agreement | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price | 83.8 |  |
Combined 2018 AZ Agreements |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price |  |  | 400.0
Combined 2018 AZ Agreements | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price | 100.7 |  |
Combined 2018 AZ Agreements | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price | 110.4 |  |
VEGF Exercise 2016 |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price |  |  | 55.1
VEGF Exercise 2016 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price | 53.7 |  |
Vertex Agreement |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price |  | $ 4.1 | $ 24.4
Vertex Agreement | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Transaction price | $ 1.6 |  |

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