Share-based compensation - Equity Incentive Plan (Details) - Plan - USD ($) |
9 Months Ended | 12 Months Ended |
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Sep. 30, 2021 |
Dec. 31, 2020 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Shares available for future grant | 63,353 | |
| Number of Shares | ||
| Outstanding at December 31, 2020 | 519,163 | |
| Granted | 299,984 | 229,984 |
| Outstanding at September 30, 2021 | 749,147 | 519,163 |
| Exercisable at September 30, 2021 | 530,977 | |
| Weighted Average Exercise Price | ||
| Outstanding at December 31, 2020 | $ 10.00 | |
| Granted | 6.85 | $ 6.85 |
| Outstanding at September 30, 2021 | 9.03 | $ 10.00 |
| Exercisable at September 30, 2021 | $ 9.92 | |
| Weighted Average Remaining Contractual Term (years) | ||
| Weighted average remaining contractual term (years) | 9 years 4 months 6 days | 9 years 11 months 23 days |
| Exercisable at September 30, 2021 | 9 years 2 months 26 days | |
| Intrinsic value of options outstanding | $ 0 |
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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. No definition available.
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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 remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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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