| Intangible assets, net - Tabular Disclosure (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021 | 
|---|---|---|
| Intangible assets, net | ||
| Intangible assets, gross | $ 5,118 | $ 5,051 | 
| Less accumulated amortization | (4,676) | (4,051) | 
| Intangible assets, net | 442 | 1,000 | 
| Acquired software licenses | ||
| Intangible assets, net | ||
| Intangible assets, gross | 4,930 | 4,842 | 
| Licensed IP rights - completed technology used in R&D | ||
| Intangible assets, net | ||
| Intangible assets, gross | $ 188 | $ 209 | 
| X | ||||||||||
| 
- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
 | 
| X | ||||||||||
| 
- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
 | 
| X | ||||||||||
| 
- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
 | 
| X | ||||||||||
| 
- References No definition available. 
 | 
| X | ||||||||||
| 
- Details 
 | 
| X | ||||||||||
| 
- Details 
 |