Note 13 - Stock-based Compensation - Share-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 |
|
| Share-Based Payment Arrangement, Expense | $ 64 | $ 207 | $ 391 | $ 1,016 |
| Research and Development Expense [Member] | ||||
| Share-Based Payment Arrangement, Expense | 13 | 70 | 154 | 398 |
| General and Administrative Expense [Member] | ||||
| Share-Based Payment Arrangement, Expense | $ 51 | $ 137 | $ 237 | $ 618 |
| 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
|