Revenues - Narrative (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024 USD ($) wholesaler	Jun. 30, 2023 USD ($) wholesaler	Jun. 30, 2024 USD ($) wholesaler	Jun. 30, 2023 USD ($) wholesaler
Disaggregation of Revenue [Line Items]
Number of wholesalers \| wholesaler	2	2	2	2
Product revenues	$ 2,464.9	$ 2,456.0	$ 4,755.4	$ 4,919.0
Distributor One
Disaggregation of Revenue [Line Items]
Percentage of revenues from major distributors	25.40%	27.00%	25.50%	27.20%
Distributor Two
Disaggregation of Revenue [Line Items]
Percentage of revenues from major distributors	12.30%	9.30%	12.00%	8.40%
Contract manufacturing, royalty and other revenue
Disaggregation of Revenue [Line Items]
Product revenues	$ 120.8	$ 176.8	$ 305.4	$ 477.0
LEQEMBI Collaboration
Disaggregation of Revenue [Line Items]
Share of non-controling interest recognized	50.00%		50.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details