Note 11 - Net Loss Per Share (Details Textual) - $ / shares |
Jun. 30, 2026 |
Dec. 31, 2025 |
Dec. 31, 2024 |
Mar. 30, 2023 |
|---|---|---|---|---|
| Series F Preferred Stock [Member] | ||||
| Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ 3.77 | $ 3.77 | $ 11.17 | $ 3.77 |