Note 4 - Prepaid Expenses - Prepaid Expenses and Other Assets (Details) - USD ($) $ in Thousands |
Mar. 31, 2021 |
Dec. 31, 2020 |
|---|---|---|
| Prepaid research and development expenses | $ 634 | $ 622 |
| Other prepaid expenses | 1,312 | 1,932 |
| Prepaid Expense, Current, Total | $ 1,946 | $ 2,554 |
| X | ||||||||||
- Definition Amount of consideration paid in advance for research and development that provides economic benefits within a future period of one year or the normal operating cycle, if longer. No definition available.
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| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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