Note 12 - Subsequent Event (Details Textual) - $ / shares |
3 Months Ended | ||
|---|---|---|---|
Apr. 01, 2022 |
Mar. 31, 2022 |
Mar. 31, 2021 |
|
| Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares) | 3,870,000 | 2,962,000 | |
| Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share) | $ 1.34 | $ 4.47 | |
| Subsequent Event [Member] | |||
| Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares) | 600,000 | ||
| Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share) | $ 1.25 | ||
| X | ||||||||||
- Definition Gross number of share options (or share units) granted during the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|