Nature of business and basis of presentation - (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net loss	$ 47,258	$ 34,693
Accumulated deficit	$ (497,737)		$ (450,479)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References + Details