Stock-based compensation - Summary of Stock Options Activity (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Shares
Outstanding as of December 31, 2020	4,552,396
Granted	1,104,666
Forfeited	(28,031)
Exercised	(421,947)
Outstanding as of December 31, 2021	5,207,084	4,552,396
Vested and expected to vest as of December 31, 2021	5,207,084
Exercisable at December 31, 2021	2,045,416
Weighted-Average Exercise Price Per Share
Outstanding as of December 31, 2020	$ 9.13
Granted	33.39
Forfeited	27.02
Exercised	6.98
Outstanding as of December 31, 2021	14.35	$ 9.13
Vested and expected to vest as of December 31, 2021	14.35
Exercisable at December 31, 2021	$ 8.06
Weighted-Average Remaining Contractual Term
Options outstanding	7 years 8 months 12 days	8 years 2 months 12 days
Vested and expected to vest as of December 31, 2021	7 years 8 months 12 days
Exercisable at December 31, 2021	6 years 2 months 12 days
Aggregate Intrinsic Value
Outstanding as of December 31, 2019	$ 167,709
Vested and expected to vest as of December 31, 2021	167,709
Exercisable at December 31, 2021	$ 78,747

Share based compensation arrangement by share based payment award options aggregate intrinsic value [Abstract]

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Share based compensation arrangement by share based payment award options weighted average remaining contractual term abstract .

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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.

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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.

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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.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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.

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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.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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