Stock-based compensation - Summary of Service Vesting-Based Stock Option Activity (Details) - Options - $ / shares	9 Months Ended
Sep. 30, 2023
Options
Outstanding as of beginning of period (in shares)	456,293
Exercised (in shares)	(175,043)
Outstanding as of end of period (in shares)	281,250
Stock options exercisable at end of period (in shares)	281,250
Wtd. Avg. Exercise Price
Outstanding as of beginning of period (in dollars per share)	$ 2.17
Exercised (in dollars per share)	2.11
Outstanding as of end of period (in dollars per share)	2.19
Stock options exercisable at end of period (in dollars per share)	$ 2.19

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.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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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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No definition available.

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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
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-Section S99
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