Share-based compensation - Schedule of Stock Option Valuation Assumptions (Details) - $ / shares |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Strike price (in dollars per share) | $ 3.96 | |||
| Employee Stock Option | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Expected volatility | 100.00% | 100.00% | ||
| Expected life, (years) | 6 years 29 days | 6 years 29 days | 6 years 29 days | |
| Expected dividend yield | 0.00% | 0.00% | ||
| Risk-free interest rate, in %, minimum | 4.07% | 3.97% | 3.73% | 3.97% |
| Risk-free interest rate, in %, maximum | 4.12% | 4.14% | 4.12% | 4.43% |
| Employee Stock Option | Minimum | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Expected volatility | 100.00% | 100.00% | ||
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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/disclosureRef
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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