Note 9 - Stockholders' Equity - Shares of Common Stock Reserved for Issuance (Details) - shares |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Common stock reserved for issuance (in shares) | 41,471,799 | 43,850,083 |
| Common Warrants [Member] | ||
| Common stock reserved for issuance (in shares) | 10,914 | 10,914 |
| The 2019 Plan [Member] | ||
| Common stock reserved for issuance (in shares) | 7,016,704 | 10,831,860 |
| The 2024 Inducement Award Plan [Member] | ||
| Common stock reserved for issuance (in shares) | 76,250 | 43,250 |
| Share-Based Payment Arrangement, Option [Member] | ||
| Common stock reserved for issuance (in shares) | 26,639,812 | 25,407,299 |
| Restricted Stock Units (RSUs) [Member] | ||
| Common stock reserved for issuance (in shares) | 6,564,721 | 5,733,306 |
| ESPP [Member] | ||
| Common stock reserved for issuance (in shares) | 1,163,398 | 1,823,454 |