Collaboration Agreements - Sanofi, Immuno-Oncology Narrative (Details) - Sanofi Collaboration Agreement, Immuno-oncology - USD ($) $ in Millions	Mar. 31, 2020	Jan. 01, 2018
Disaggregation of Revenue [Line Items]
Maximum shares the collaborator could sell (in shares)	740,914	1,400,000
Unsatisfied obligation	$ 1,087

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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