Income taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Line Items]
Loss carryforwards	$ 12,537	$ 31,841
Deferred tax assets valuation allowance	26,339	41,929	$ 43,467	$ 45,661
Decrease in valuation allowance	15,600
Unrecognized tax benefits that, if recognized, would impact effective tax rate	6,400	6,800
Recognized expense/income from the release of penalty reserves	200	700	$ 0
Accrued interest expense and penalties payable related to unrecognized tax benefits	900	$ 700
Estimated decrease in gross unrecognized tax positions within the next 12 months, maximum	2,100
State
Income Taxes [Line Items]
Tax credit carryforward	5,100
Loss carryforwards	9,100
Decrease in valuation allowance	14,300
Federal
Income Taxes [Line Items]
Loss carryforwards	$ 1,800