Collaborative and Other Relationships - Eisai (Details) $ in Millions	Sep. 30, 2023 USD ($)
LEQEMBI Collaboration
Collaborative arrangements and non-collaborative arrangement transactions
Payable Due To Termination Agreement	$ 31.0

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479402/808-10-50-1

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration