Collaborative and Other Relationships - Eisai (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Collaborative arrangements and non-collaborative arrangement transactions
Product revenues	$ 2,463.0	$ 2,531.8
LEQEMBI Collaboration
Collaborative arrangements and non-collaborative arrangement transactions
Product revenues	(18.9)	$ 0.0
Payable Due To Termination Agreement	$ 31.0

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