Note 7 - Earnings Per Share - Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Basic weighted-average shares (in shares)	24,701,000	24,187,000	24,656,000	24,183,000
Conversion of unsecured loan notes (in shares)
Unexercised options and unvested RSUs (in shares)	419,000
Diluted weighted-average shares (in shares)	25,120,000	24,187,000	24,656,000	24,183,000