Note 3 - Net Loss Per Share - Antidilutive Securities (Details) - shares |
12 Months Ended | |
|---|---|---|
Dec. 31, 2022 |
Dec. 31, 2021 |
|
| Total potential dilutive shares (in shares) | 69,124,717 | 33,910,681 |
| Share-Based Payment Arrangement, Option [Member] | ||
| Total potential dilutive shares (in shares) | 12,741,394 | 5,977,179 |
| Performance Shares [Member] | ||
| Total potential dilutive shares (in shares) | 31,850,000 | 3,790,755 |
| Restricted Stock [Member] | ||
| Total potential dilutive shares (in shares) | 388,750 | 0 |
| Shares Reserved for Convertible Notes [Member] | ||
| Total potential dilutive shares (in shares) | 8,215,706 | 8,213,880 |
| Warrant [Member] | ||
| Total potential dilutive shares (in shares) | 15,928,867 | 15,928,867 |