Collaboration Agreements - Massachusetts Eye and Ear Infirmary and The Schepens Eye Research Institute, Inc. (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
MEE
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
License fees due under agreement	$ 0.4

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.

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Balance Type:	na
Period Type:	duration