Note 7 - Stockholders' Equity- Stock-based Compensation Expense (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Stock-based compensation | $ 175 | $ 192 | $ 360 | $ 383 |
| Research and Development Expense [Member] | ||||
| Stock-based compensation | 31 | 45 | 71 | 90 |
| General and Administrative Expense [Member] | ||||
| Stock-based compensation | $ 144 | $ 147 | $ 289 | $ 293 |
| X | ||||||||||
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|