| Stockholders equity - Offerings (Details) - 2022 Sales Agreement - USD ($) | 12 Months Ended | |
|---|---|---|
| Apr. 08, 2022 | Dec. 31, 2024 | |
| Shareholders' equity | ||
| Remaining amount under the Sales Agreement | $ 156,228,841 | |
| Aggregate offering price of ADS shares under At The Market sales agreement | 163,669,056 | |
| Net proceeds | $ 29,155,317 | |
| Maximum | ||
| Shareholders' equity | ||
| Aggregate offering price of ADS shares under At The Market sales agreement | $ 200,000,000 | |
| ADR [Member] | ||
| Shareholders' equity | ||
| Sold shares represented by American Depositary Shares (in shares) | 27,278,176 | 
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- Definition Aggregate offering price of ADS shares that may be issued and sole under the At The Market sales agreement. No definition available. 
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- Definition Aggregate offering price of ADS shares that may be issued and sold under the At The Market sales agreement. No definition available. 
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- Definition Represents the remaining amount available under the sales agreement. No definition available. 
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- Definition Number of American Depositary Shares representing shares sold during the period. No definition available. 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef 
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- Definition The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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