| Financial instruments - Collaboration and License Agreement (Details) | 12 Months Ended | |
|---|---|---|
| Dec. 31, 2022  USD ($)  customer | Dec. 31, 2021  USD ($) | |
| Financial instruments | ||
| Number of customers | customer | 3 | |
| Trade receivables | $ 7,435,000 | $ 752,000 | 
| Impairment losses | 0 | |
| Amounts past due | $ 0 | 
| X | ||||||||||
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- Definition Number of customers. No definition available. 
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| X | ||||||||||
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- Definition Amounts past due. No definition available. 
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| X | ||||||||||
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- Definition Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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| X | ||||||||||
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
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- References No definition available. 
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