Note 2 - Summary of Significant Accounting Policies - Antidilutive Securities (Details) - shares |
6 Months Ended | |
|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Antidilutive securities (in shares) | 10,324,294 | 1,780,350 |
| Warrant [Member] | ||
| Antidilutive securities (in shares) | 3,449,634 | 1,460,199 |
| Share-Based Payment Arrangement, Option [Member] | ||
| Antidilutive securities (in shares) | 273,257 | 320,151 |
| Convertible Debt [Member] | ||
| Antidilutive securities (in shares) | 1,910,926 | 0 |
| Series V Preferred Stock [Member] | ||
| Antidilutive securities (in shares) | 4,690,477 | 0 |