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 |