Note 2 - Summary of Significant Accounting Policies - Outstanding Stock Warrants Excluded from the Diluted Net Loss Per Share Computation (Details) - shares shares in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Anti-dilutive securities (in shares) | 189,249 | 870 | 15,450 | 870 |
| Series B Preferred Stock [Member] | ||||
| Anti-dilutive securities (in shares) | 0 | 3 | 0 | 3 |
| Share-Based Payment Arrangement, Option [Member] | ||||
| Anti-dilutive securities (in shares) | 21,703 | 1 | 15,446 | 1 |
| October 2025 Pre-Funded Warrants [Member] | ||||
| Anti-dilutive securities (in shares) | 167,546 | 866 | 4 | 866 |