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Percentage of annual increase in reserves on total number of ordinary shares outstanding.

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Period for vesting equity-based award in equal monthly installment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Aggregate number of common shares reserved for future issuance.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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No definition available.

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Number of shares authorized for issuance under share-based payment arrangement.

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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.

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

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of new stock issued during the period.

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Share-based compensation (Details) - shares	1 Months Ended		12 Months Ended
Share-based compensation (Details) - shares	Jun. 30, 2020	May 31, 2019	Dec. 31, 2021	Jan. 01, 2022	Dec. 31, 2020
Stock option
Share-based compensation.
Shares outstanding	3,654,012		4,603,486		3,736,663
Employee Share Purchase Plan
Share-based compensation.
Percentage of annual increase in reserves on total number of ordinary shares outstanding		1.00%
Number of ordinary shares reserved for issuance		215,000		295,793
Number of shares available for issuance		430,000
Percentage of ordinary shares at a price per share equal to the fair market value on offering date or purchase date		85.00%
Increase in number of ordinary shares reserved for issuance			605,882
2020 Plan
Share-based compensation.
Number of shares reserved for issuance	4,773,557		5,052,993
Shares issued (in shares)	574,679
Shares outstanding			1,780,353
Percentage of annual increase in reserves on total number of ordinary shares outstanding	5.00%
2020 Plan \| Stock option
Share-based compensation.
Contractual life	10 years
Number of shares reserved for issuance				1,478,968
2020 Plan \| Stock option \| Non-employee Director
Share-based compensation.
Vesting period	3 years
2020 Plan \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage	25.00%
2020 Plan \| Stock option \| 36 equal monthly installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards	36 months
2020 Plan \| Stock option \| Employee
Share-based compensation.
Vesting period	4 years
2019 Plan
Share-based compensation.
Number of shares reserved for issuance	544,866
2019 Plan \| Stock option
Share-based compensation.
Shares outstanding			2,200,486
Pre-IPO Share Options and restricted shares \| Stock option
Share-based compensation.
Contractual life			10 years
Pre-IPO Share Options and restricted shares \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage			25.00%
Pre-IPO Share Options and restricted shares \| Stock option \| 36 equal monthly installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards			36 months
Pre-IPO Share Options and restricted shares \| Minimum \| Stock option
Share-based compensation.
Vesting period			3 years
Pre-IPO Share Options and restricted shares \| Maximum \| Stock option
Share-based compensation.
Vesting period			4 years