Stock-based compensation - Compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Stock-based compensation
Stock-based compensation	$ 14,787	$ 14,785	$ 11,153
Research and development
Stock-based compensation
Stock-based compensation	6,138	6,039	3,585
General and administrative
Stock-based compensation
Stock-based compensation	$ 8,649	$ 8,746	$ 7,568

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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+ Details