Accounting policies - Comparative amounts (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenue	$ 33,591,079	$ 32,479,158	$ 67,306,464	$ 72,168,548
Services
Revenue	$ 11,448,202	11,922,469	$ 21,526,470	29,340,080
Services \| Design and consulting revenue \| Previously issued
Revenue		679,462		853,262
Services \| Construction revenue \| Reclassified
Revenue		$ 679,462		$ 853,262

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details