Basic and diluted loss per share - Antidilutive securities excluded from diluted calculation (Details) - shares	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Employee Stock Option
Antidilutive securities excluded from diluted calculation
Antidilutive securities excluded from diluted calculation	1,704,500	730,834
Lender warrants
Antidilutive securities excluded from diluted calculation
Antidilutive securities excluded from diluted calculation	437,177	187,177

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482662/260-10-50-1

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration