Note 7 - Earnings Per Share - Earnings Per Share (Details) - shares	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Basic weighted-average shares (in shares)	30,296,000	30,267,000
Conversion of unsecured loan notes (in shares)	0	0
Unexercised options and unvested RSUs (in shares)	0	0
Diluted weighted-average shares (in shares)	30,296,000	30,267,000

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 42
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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