Note 7 - Earnings Per Share - Earnings Per Share (Details) - shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Basic weighted-average shares (in shares)	27,510,000	24,597,000
Conversion of unsecured loan notes (in shares)
Unexercised options and unvested RSUs (in shares)	227,000
Diluted weighted-average shares (in shares)	27,737,000	24,597,000

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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