Note 1 - Organization and Significant Accounting Policies - Summary of Earnings (Loss) Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Basic weighted-average shares (in shares)	30,289,000	29,585,000
Conversion of unsecured loan notes (in shares)	0	0
Unexercised options and unvested restricted stock units (in shares)	0	109,000
Diluted weighted-average shares (in shares)	30,289,000	29,694,000