Note 4 - Prepaid Expenses - Prepaid Expenses and Other Assets (Details) - USD ($) $ in Thousands |
Mar. 31, 2023 |
Dec. 31, 2022 |
|---|---|---|
| Prepaid Expense and Other Assets [Abstract] | ||
| Prepaid research and development expenses | $ 1,208 | $ 1,271 |
| Prepaid insurance | 684 | 893 |
| Other prepaid expenses | 155 | 139 |
| Total | $ 2,047 | $ 2,303 |
| 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
|
| X | ||||||||||
- References No definition available.
|
| 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://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for insurance that provides 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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