Share-based compensation - Stock options narratives (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Share-based compensation
Total stock compensation expense	$ 4,400,000
Stock options
Share-based compensation
Aggregate intrinsic value of stock options outstanding	10,561,716		$ 7,460,132
Total stock compensation expense	51,079	$ 41,422	195,830
Unrecognized stock compensation expense	$ 602,264		$ 608,826
Weighted average period for unrecognized stock compensation expense	2 years 9 months 21 days		3 years

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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

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Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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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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No definition available.

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

+ References

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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