Collaboration, License, and Other Agreements - U.S. Government Narrative (Details) - US Government - REGEN-COV - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Jan. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Maximum transaction agreement payments		$ 465.9
Subsequent Event
Disaggregation of Revenue [Line Items]
Maximum transaction agreement payments	$ 2,625.0

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.

No definition available.

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Balance Type:	na
Period Type:	duration