Note 10 - Stock-based Compensation - Phantom Stock Units (Details) - Phantom Share Units (PSUs) [Member] |
12 Months Ended |
|---|---|
|
Dec. 31, 2021
$ / shares
shares
| |
| Outstanding, shares (in shares) | shares | 634,759 |
| Outstanding, grant date fair value (in dollars per share) | $ / shares | $ 3.86 |
| Granted, shares (in shares) | shares | 1,887,486 |
| Granted, grant date fair value (in dollars per share) | $ / shares | $ 7.04 |
| Vested, shares (in shares) | shares | (173,961) |
| Vested, grant date fair value (in dollars per share) | $ / shares | $ 3.86 |
| Canceled or forfeited, shares (in shares) | shares | (94,884) |
| Canceled or forfeited, grant date fair value (in dollars per share) | $ / shares | $ 4.86 |
| Outstanding, shares (in shares) | shares | 2,253,400 |
| Outstanding, grant date fair value (in dollars per share) | $ / shares | $ 6.47 |