Note 7 - Earnings Per Share - Shares Used to Calculate Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Weighted average number of shares used in computation of basic earnings per share: (in shares)	56,710	56,063
Additional shares from the assumed exercise of employee stock awards (in shares)	394	303
Weighted average number of shares used in computation of diluted earnings per share (in shares)	57,104	56,366

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480454/718-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Topic 260
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Section 50
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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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