Note 2 - Summary of Significant Accounting Policies - Antidilutive Securities Excluded From Computation of Earnings Per Share (Details) - shares |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Jun. 30, 2023 |
Jun. 30, 2022 |
Jun. 30, 2023 |
Jun. 30, 2022 |
|||
| Total potential dilutive securities (in shares) | 6,605,262 | 5,154,251 | 6,481,403 | 5,307,642 | ||
| Share-Based Payment Arrangement, Option [Member] | ||||||
| Total potential dilutive securities (in shares) | [1] | 417,749 | 1,020,949 | 704,316 | 1,023,814 | |
| Restricted Stock Units (RSUs) [Member] | ||||||
| Total potential dilutive securities (in shares) | 6,181,141 | 4,126,930 | 5,770,715 | 4,277,456 | ||
| Warrant [Member] | ||||||
| Total potential dilutive securities (in shares) | 6,372 | 6,372 | 6,372 | 6,372 | ||
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