Note 9 - Incentive Plans - Number of Shares Available for Grant Pursuant to Long-term Incentive Plan (Details) - shares	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Shares subject to awards issued under plan (in shares)	(11,503,727)	(11,517,228)	(9,983,727)
The 2020 Long-term Incentive Plan [Member]
Approved and authorized shares (in shares)	14,341,882	14,340,324
Shares subject to awards issued under plan (in shares)	(13,755,690)	(13,769,191)
Shares available for future grant (in shares)	586,192	571,133