Note 2 - Accounting Policies - Earnings Per Share (Details) - shares	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Weighted average number of common shares used for basic EPS (in shares)	30,866,188	32,312,000	31,259,594	32,390,777
Effect of dilutive stock options and restricted and deferred stock unit awards (in shares)	511,244	0	0	667,229
Weighted average number of common shares and dilutive potential common stock used for dilutive EPS (in shares)	31,377,432	32,312,000	31,259,594	33,058,006

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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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

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-Publisher FASB
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-Topic 260
-SubTopic 10
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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://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 260
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