Note 12 - Stock-based Compensation - Share-based Payment Expense (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2022 |
Dec. 31, 2021 |
|
| Share-Based Payment Arrangement, Expense | $ 5,207 | $ 12,949 |
| Research and Development Expense [Member] | ||
| Share-Based Payment Arrangement, Expense | 2,218 | 3,789 |
| General and Administrative Expense [Member] | ||
| Share-Based Payment Arrangement, Expense | $ 2,989 | $ 9,160 |
| 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
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| X | ||||||||||
- Details
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