Note 6 - Stockholders' Equity - Basic and Diluted Earnings Per Share Calculation (Details) - shares shares in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Weighted average shares outstanding for basic calculation (in shares)	14,531	14,236
Dilutive effect of restricted stock (in shares)	43
Weighted average shares outstanding for diluted calculation (in shares)	14,574	14,236

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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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.

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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.

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