Share-based compensation - Summary of Status of Company's Stock Option Plan (Details) - $ / shares	6 Months Ended	12 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Shares
-Granted	354,838	415,478
Stock Option Plan
Shares
Outstanding at beginning of period	2,604,023	5,329,515	5,329,515
-Cancelled	(750)		(133,257)
-Exercised	(327,840)		(3,076,489)
-Granted	354,838		484,254
Outstanding at end of period	2,630,271		2,604,023
Weighted Average Exercise Price
Outstanding at beginning of period	$ 1.03	$ 1.06	$ 1.06
-Cancelled	4.20		2.02
-Exercised	1.12		1.16
-Granted	4.09		1.82
Outstanding at end of period	$ 1.43		$ 1.03

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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.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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- Definition

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

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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.

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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.

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

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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.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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