Intangible assets - Costs and accumulated amortization (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Cost
Finite-lived intangible assets, gross	$ 6,008,390	$ 6,008,390
Accumulated amortization
Finite-lived intangible assets, accumulated amortization	(3,311,575)	(2,655,205)
Intangible assets, net	2,696,815	3,353,185
Trade names
Cost
Finite-lived intangible assets, gross	3,096,900	3,096,900
Accumulated amortization
Finite-lived intangible assets, accumulated amortization	(1,313,075)	(1,106,615)
Non-compete agreement
Cost
Finite-lived intangible assets, gross	268,590	268,590
Accumulated amortization
Finite-lived intangible assets, accumulated amortization	(67,147)	(13,430)
Customer relationships
Cost
Finite-lived intangible assets, gross	442,900	442,900
Accumulated amortization
Finite-lived intangible assets, accumulated amortization	(36,908)	(7,382)
Facility management contracts
Cost
Finite-lived intangible assets, gross	2,200,000	2,200,000
Accumulated amortization
Finite-lived intangible assets, accumulated amortization	$ (1,894,445)	$ (1,527,778)