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Dispositions (Details Textual) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | ---
Apr. 30, 2024 | Apr. 30, 2022 | Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023 | Mar. 31, 2022
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |
Accounts payable |  |  | $ 354.5 |  | $ 354.5 |  | $ 403.3 |
Gain on sale of priority review voucher, net |  |  | $ 88.6 | $ 0.0 | $ 88.6 | $ 0.0 |  |
Ionis |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |
Proceeds from sale of intangible assets | $ 103.0 |  |  |  |  |  |  |
Accounts payable | $ 14.4 |  |  |  |  |  |  |
Samsung Bioepis |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |
Equity, ownership interest |  |  | 49.90% |  | 49.90% |  |  | 49.90%
Equity Method Investment, Amount Sold |  | $ 2,300.0 |  |  |  |  |  |
Samsung Bioepis |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |
Proceeds from divestiture of interest in joint venture |  | 1,000.0 |  |  |  |  |  |
Payables to divestiture of interest in joint venture |  | 1,300.0 |  |  |  |  |  |
Samsung Bioepis | Payment Due At First Anniversary |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |
Payables to divestiture of interest in joint venture |  | 812.5 |  |  |  |  |  |
Gain (loss) on sale |  |  |  | 2.6 |  | 13.7 |  |
Samsung Bioepis | Payment Due At Second Anniversary |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |
Payables to divestiture of interest in joint venture |  | $ 437.5 |  |  |  |  |  |
Gain (loss) on sale |  |  | $ 1.4 | $ 3.6 | $ 7.5 | $ 9.8 |  |

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