Note 7 - Earnings Per Share - Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Basic weighted-average shares (in shares)	30,296,000	30,264,000	30,287,000	29,356,000
Conversion of unsecured loan notes (in shares)	0	0	0	0
Unexercised options and unvested RSUs (in shares)	75,000	71,000	0	126,000
Diluted weighted-average shares (in shares)	30,371,000	30,335,000	30,287,000	29,482,000