Income taxes - Effective Tax Rate (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Effective income tax rate	(0.70%)	0.20%	(0.90%)	(1.10%)
Enacted tax rate	25.80%		25.80%
Deferred tax (benefit) expense			$ (1,263)	$ 3,560
United States and France
Deferred tax (benefit) expense	$ (300)		$ (1,300)
United States and Netherland
Deferred tax (benefit) expense		$ 100		3,600
Netherland
Deferred tax (benefit) expense		$ 0		$ 3,000