Income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Operating Loss Carryforwards [Line Items]
Income tax expense	$ 0	$ 0
Increase in valuation allowance	66,900	$ 9,200
Federal operating loss	119,900
State net operating loss	95,600
Net operating loss generated not subject to expiration	$ 102,800
Percentage of taxable income offset from net operating loss	80.00%
R&D tax credits	$ 200
Federal
Operating Loss Carryforwards [Line Items]
Federal tax	$ 9,900