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Collaborative and Other Relationships - Ionis (Details) - USD ($) shares in Millions, $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Jun. 30, 2018 | Dec. 31, 2017 | Sep. 30, 2013 | Dec. 31, 2012 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2016 | Dec. 31, 2015
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Cost of sales, excluding amortization and impairment of acquired intangible assets |  |  |  |  |  |  | $ 1,805.2 | $ 1,955.4 | $ 1,816.3 |  |
Research and development |  |  |  |  |  |  | 3,990.9 | 2,280.6 | 2,597.2 |  |
Ionis Pharmaceuticals |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
License fee |  |  |  |  | $ 70.0 | $ 70.0 |  |  |  |  |
Expected license fee and regulatory milestone payments |  |  |  |  | $ 130.0 | 130.0 |  |  |  |  |
Upfront payment for collaboration agreement |  |  | $ 375.0 |  |  | 30.0 |  |  |  |  |
Total aducanumab collaboration third party milestone expense | $ 155.0 |  |  |  |  | $ 10.0 |  |  |  |  |
Research and development |  |  | $ 324.1 |  |  |  | 11.3 | 30.0 |  |  | $ 10.0
Research and development expense asset acquired | $ 45.0 |  |  |  |  |  |  |  |  |  |
Term of collaboration agreement |  |  | 10 years |  | 6 years |  |  |  |  |  |
Total payment to enter collaboration agreement |  |  | $ 1,000.0 |  |  |  |  |  |  |  |
Investment in common stock, shares purchased (in shares) |  |  | 11.5 |  |  |  |  |  |  |  |
Purchase of common stock |  |  | $ 625.0 |  |  |  |  |  |  |  |
Prepaid research and discovery services |  |  | 50.9 |  |  |  |  |  |  |  |
Investment in common stock, value |  |  | 462.9 |  |  |  |  |  |  |  |
Premium on purchase of common stock |  |  | 162.1 |  |  |  |  |  |  |  |
Estimated additional payments upon achievement of development and commercial milestones |  |  |  | $ 260.0 |  |  |  |  |  |  |
Upfront and milestone payments made to collaborative partner |  |  |  | 25.0 |  |  |  |  |  |  |
Expected additional milestone payments when certain sales threshold is met |  |  |  | $ 800.0 |  |  |  |  |  |  |
Ionis Pharmaceuticals | SOD1 |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Research and development |  |  |  |  |  |  | 28.0 | 20.0 | 18.0 |  |
Estimated additional payments upon achievement of development and commercial milestones |  | $ 55.0 |  |  |  |  |  |  |  |  |
Upfront and milestone payments made to collaborative partner |  | $ 35.0 |  |  |  |  |  |  |  |  |
Ionis Pharmaceuticals | SPINRAZA |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Cost of sales, excluding amortization and impairment of acquired intangible assets |  |  |  |  |  |  | $ 286.6 | $ 293.0 | $ 238.0 |  |
Ionis Pharmaceuticals | Minimum |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Estimated additional payments upon achievement of development and commercial milestones |  |  | 125.0 |  |  |  |  |  |  |  |
Ionis Pharmaceuticals | Minimum | SPINRAZA |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Percentage of royalties as per collaboration |  |  |  |  |  |  | 11.00% |  |  | 11.00% |
Ionis Pharmaceuticals | Maximum |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Estimated additional payments upon achievement of development and commercial milestones |  |  | $ 270.0 |  |  |  |  |  |  |  |
Ionis Pharmaceuticals | Maximum | SPINRAZA |  |  |  |  |  |  |  |  |  |  |
Collaborative arrangements and non-collaborative arrangement transactions |  |  |  |  |  |  |  |  |  |  |
Percentage of royalties as per collaboration |  |  |  |  |  |  | 15.00% |  |  | 15.00% |

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