Income taxes - Operating Loss Carryforwards (Details) - USD ($)	3 Months Ended	9 Months Ended
	Mar. 31, 2026	Sep. 30, 2025	Dec. 31, 2025
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 22,126,619		$ 21,770,284
Unrecognized tax benefits	0		0
Domestic Tax Jurisdiction
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	11,787,208		12,171,811
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 10,339,411		$ 9,598,473
Net operating loss carryforwards, subject to expiration, period	20 years	20 years