Collaborative and Other Relationships - Merz Therapeutics (Previously Acorda Therapeutics, Inc.) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Acorda
Collaborative arrangements and non-collaborative arrangement transactions
Expense reflected within statements of income	$ 52.4	$ 55.2	$ 46.1

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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Balance Type:	na
Period Type:	duration