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Collaborative and Other Relationships - Collaborations (Details) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Aug. 31, 2021 | Jun. 30, 2021 | Mar. 31, 2022 | Dec. 31, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2022 | Dec. 31, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Research and Development Expense (Excluding Acquired in Process Cost) |  |  | $ 551.7 |  |  | $ 514.2 |  |  |
Cost of sales, excluding amortization and impairment of acquired intangible assets |  |  | 753.9 |  |  | 478.1 |  |  |
(Gain) loss on equity method investments |  |  | (3.3) |  |  | (18.2) |  |  |
Maximum | Forecast |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  | $ 335.0 |
Samsung Bioepis |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
(Gain) loss on equity method investments |  |  | 4.0 |  |  | 11.0 |  |  |
Loss recorded on Samsung Bioepis joint venture |  |  | 3.3 |  |  | 18.2 |  |  |
Amortization |  |  | 7.3 |  |  | $ 7.2 |  |  |
ADUHELM |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Cost of sales, excluding amortization and impairment of acquired intangible assets |  |  | $ 275.0 |  |  |  |  |  |
Eisai |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Percentage of future development costs related to Eisai |  |  | 45.00% |  |  | 45.00% |  |  |
Collaboration agreement term |  |  | 10 years |  |  |  |  |  | 5 years
Cost of Goods Sold, Capacity Charges |  |  | $ 45.0 |  |  |  |  |  |
(Gain) loss on equity method investments |  |  | 181.7 |  |  |  |  |  |
Due from Related Parties |  |  | 402.7 | $ 285.4 |  |  |  |  | $ 285.4
Due to Related Parties |  |  | 36.5 | 46.5 |  |  |  |  | 46.5
Eisai | BAN2401 and Elenbecestat |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense Incurred By Collaboration |  |  | 77.0 |  |  | $ 55.5 |  |  |
Expense reflected within statements of income |  |  | 38.5 |  |  | 27.7 |  |  |
Eisai | ADUHELM |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Additional milestone payment |  | $ 100.0 |  |  |  |  |  |  |
(Gain) loss on equity method investments |  |  | $ 160.0 | 59.0 | $ 45.0 | 45.0 |  |  |
Samsung Bioepis |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Upfront and milestone payments made to collaborative partner |  |  |  |  |  |  | $ 100.0 |  |
Collaboration agreement term |  |  | 5 years |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  | $ 63.0 |  |
Due from Related Parties |  |  | $ 5.8 | 4.1 |  |  |  |  | 4.1
Due to Related Parties |  |  | $ 102.5 | $ 148.7 |  |  |  |  | 148.7
Sangamo Therapeutics, Inc. Agreement |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Term of collaboration agreement |  |  | 5 years |  |  |  |  |  |
Other research and discovery |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Research and Development Expense (Excluding Acquired in Process Cost) |  |  | $ 19.5 |  |  | 1.0 |  |  |
InnoCare Pharma Limited (InnoCare) Agreement |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Upfront and milestone payments made to collaborative partner | $ 125.0 |  |  |  |  |  |  |  |
Contingent additional milestone payment | $ 812.5 |  |  |  |  |  |  |  |
Research and development | Eisai | ADUHELM |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 44.2 |  |  | 47.0 |  |  |
Expense reflected within statements of income |  |  | 24.3 |  |  | 25.8 |  |  |
Research and development | Denali Therapeutics |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 14.9 |  |  | 15.4 |  |  |
Expense reflected within statements of income |  |  | 8.9 |  |  | 9.2 |  |  |
Research and development | Samsung Bioepis |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 8.3 |  |  |  |  |  | 4.8
Expense reflected within statements of income |  |  | 5.5 |  |  |  |  |  | $ 4.2
Research and development | Sage Therapeutics Inc. |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 38.7 |  |  | 39.8 |  |  |
Expense reflected within statements of income |  |  | 19.4 |  |  | 19.9 |  |  |
Research and development | UCB Pharma S.A. [Member] |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 17.6 |  |  | 16.9 |  |  |
Expense reflected within statements of income |  |  | 8.8 |  |  | 8.4 |  |  |
Selling, general and administrative | Eisai | BAN2401 and Elenbecestat |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 15.9 |  |  | 5.7 |  |  |
Expense reflected within statements of income |  |  | 8.0 |  |  | 2.9 |  |  |
Selling, general and administrative | Eisai | ADUHELM |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 95.0 |  |  | 111.8 |  |  |
Expense reflected within statements of income |  |  | 50.9 |  |  | 60.3 |  |  |
Selling, general and administrative | Sage Therapeutics Inc. |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |
Expense incurred by the collaboration |  |  | 18.4 |  |  | 5.3 |  |  |
Expense reflected within statements of income |  |  | $ 9.2 |  |  | $ 2.7 |  |  |

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