Summary of significant accounting policies - Stock-based compensation (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Other long-term liabilities \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of restricted common stock liability	$ 0.3	$ 0.5

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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