Note 9 - Stockholders' Equity - Shares of Common Stock Reserved for Issuance 1 (Details) - shares |
Mar. 31, 2026 |
Dec. 31, 2025 |
Dec. 31, 2024 |
Feb. 27, 2024 |
|---|---|---|---|---|
| Common stock reserved for issuance (in shares) | 42,413,698 | 43,850,083 | 45,575,342 | |
| Common Warrants [Member] | ||||
| Common stock reserved for issuance (in shares) | 10,914 | 10,914 | 140,596 | |
| The 2019 Plan [Member] | ||||
| Common stock reserved for issuance (in shares) | 6,043,856 | 10,831,860 | 18,046,374 | |
| The 2024 Inducement Award Plan [Member] | ||||
| Common stock reserved for issuance (in shares) | 76,250 | 43,250 | 1,603,750 | 3,000,000 |
| Share-Based Payment Arrangement, Option [Member] | ||||
| Common stock reserved for issuance (in shares) | 27,767,619 | 25,407,299 | 20,405,239 | |
| Restricted Stock Units (RSUs) [Member] | ||||
| Common stock reserved for issuance (in shares) | 6,691,605 | 5,733,306 | 3,016,481 | |
| ESPP [Member] | ||||
| Common stock reserved for issuance (in shares) | 1,823,454 | 1,823,454 | 2,362,902 |