Property and equipment, net - Components of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 159	$ 159
Less accumulated depreciation	(41)	(40)
Property and equipment, net	118	119
Computers and Equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	11	11
Manufacturing Tools and Dies
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 148	$ 148