Note 11 - Benefit Plans - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
[1] | Sep. 30, 2025 |
|||||
| Share-Based Payment Arrangement, Expense | $ 1,079 | $ 1,703 | $ 3,431 | $ 5,017 | |||||
| Total stock-based compensation | 1,079 | 1,703 | 3,431 | 5,017 | |||||
| Share-Based Payment Arrangement, Option [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | 1,079 | 1,703 | 3,431 | 5,146 | |||||
| Total stock-based compensation | 1,079 | 1,703 | 3,431 | 5,146 | |||||
| Restricted Stock Awards [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | [2] | 0 | 0 | 0 | (129) | ||||
| Total stock-based compensation | [2] | 0 | 0 | 0 | (129) | ||||
| General and Administrative [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | 555 | 949 | 1,667 | 2,717 | |||||
| Total stock-based compensation | 555 | 949 | 1,667 | 2,717 | |||||
| Research and Development [Member] | |||||||||
| Share-Based Payment Arrangement, Expense | 524 | 754 | 1,764 | 2,300 | |||||
| Total stock-based compensation | $ 524 | $ 754 | $ 1,764 | $ 2,300 | |||||
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