Note 11 - Benefit Plans - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
[1] | Jun. 30, 2025 |
|||||
| Share-Based Payment Arrangement, Expense | $ 1,040 | $ 1,367 | $ 2,352 | $ 3,314 | |||||
| Total stock-based compensation | 1,040 | 1,367 | 2,352 | 3,314 | |||||
| Share-Based Payment Arrangement, Option [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | 1,040 | 1,496 | 2,352 | 3,443 | |||||
| Total stock-based compensation | 1,040 | 1,496 | 2,352 | 3,443 | |||||
| Restricted Stock Awards [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | [2] | 0 | (129) | 0 | (129) | ||||
| Total stock-based compensation | [2] | 0 | (129) | 0 | (129) | ||||
| General and Administrative [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | 514 | 767 | 1,112 | 1,768 | |||||
| Total stock-based compensation | 514 | 767 | 1,112 | 1,768 | |||||
| Research and Development [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | 526 | 600 | 1,240 | 1,546 | |||||
| Total stock-based compensation | $ 526 | $ 600 | $ 1,240 | $ 1,546 | |||||
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