Note 11 - Stock-based Compensation - Share-based Payment Expense (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2021 |
Sep. 30, 2020 |
|
| Share-based payment expense | $ 1,828 | $ 4,905 | $ 10,635 | $ 17,007 |
| Research and Development Expense [Member] | ||||
| Share-based payment expense | 609 | 1,051 | 2,985 | 2,784 |
| General and Administrative Expense [Member] | ||||
| Share-based payment expense | $ 1,219 | $ 3,854 | $ 7,650 | $ 14,223 |
| X | ||||||||||
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|