Note 7 - Earnings Per Share - Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Basic weighted-average shares (in shares)	30,267,000	27,510,000
Conversion of unsecured loan notes (in shares)	0	0
Unexercised options and unvested RSUs (in shares)	0	227,000
Diluted weighted-average shares (in shares)	30,267,000	27,737,000