Leases - Schedule of supplemental balance sheet information (Detail) - USD ($) |
Sep. 30, 2026 |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|---|
| Leases [Abstract] | |||
| Operating right-of-use assets | $ 581,000 | $ 704,854 | $ 648,136 |
| Current portion of operating lease liabilities | 184,000 | 164,940 | 160,016 |
| Operating lease liabilities, net of current portion | 429,000 | 569,881 | 516,838 |
| Total operating lease liabilities | $ 613,000 | $ 734,821 | $ 676,854 |