Related party transactions (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Atlas Venture Life Science Advisors, LLC
Related Party Transaction
Outstanding liability to related party	$ 0

Carrying amount as of the balance sheet date of obligations due all related parties.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Period Type:	instant