Share-based compensation - Equity Incentive Plan (Details) - Plan - $ / shares |
9 Months Ended | 12 Months Ended | |
|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
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| Number of Shares | |||
| Outstanding at the beginning of the period | 1,105,578 | ||
| Granted | 741,500 | 109,853 | |
| Forfeited or expired | (851) | ||
| Outstanding at the end of the period | 1,846,227 | 1,105,578 | |
| Exercisable at the end of the period | 125,596 | ||
| Weighted Average Exercise Price | |||
| Outstanding at the beginning of the period | $ 12.8 | ||
| Granted | 2.657 | $ 4.711 | |
| Forfeited or expired | 98.8 | ||
| Outstanding at the end of the period | 8.66 | $ 12.8 | |
| Exercisable at the end of the period | $ 64.26 | ||
| Weighted Average Remaining Contractual Term (Years) | |||
| Weighted average remaining contractual term (years) | 9 years 1 month 17 days | 9 years 7 months 20 days | |
| Exercisable at the end of the period (years) | 6 years 9 months 29 days | ||
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- References No definition available.
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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Gross number of share options (or share units) granted during the period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. 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 Weighted-average contractual term remaining for vested portion of option outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted-average contractual term remaining for option award outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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