| Intangible assets, net - Tabular Disclosure (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | 
|---|---|---|
| Intangible assets, net | ||
| Intangible assets, gross | $ 5,485 | $ 5,118 | 
| Less accumulated amortization | (5,155) | (4,676) | 
| Intangible assets, net | 330 | 442 | 
| Acquired software licenses | ||
| Intangible assets, net | ||
| Intangible assets, gross | 5,288 | 4,930 | 
| Licensed IP rights - completed technology used in R&D | ||
| Intangible assets, net | ||
| Intangible assets, gross | $ 197 | $ 188 | 
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- 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 
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- 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 
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- 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 
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- References No definition available. 
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- Details 
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- Details 
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