Commitments - License agreements (Details) - License agreements $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) item	Mar. 31, 2019 USD ($)
Commitments
Number of biotechnology companies where Company has licensed intellectual property \| item	2
Milestone payments \| $	$ 0	$ 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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