Note 15 - Stock Based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Thousands |
12 Months Ended | |
---|---|---|
Dec. 31, 2022 |
Dec. 31, 2021 |
|
Stock compensation expense | $ 6,788 | $ 5,267 |
General and Administrative Expense [Member] | ||
Stock compensation expense | 4,395 | 3,676 |
Research and Development Expense [Member] | ||
Stock compensation expense | $ 2,393 | $ 1,591 |