Note 2 - Summary of Significant Accounting Policies - Weighted Average Common Shares (Details) - shares	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Weighted average common shares outstanding - basic (in shares)	10,326,309	10,264,565
Potentially dilutive securities:
Unvested shares of restricted stock and stock options (in shares)	38,997	30,772
Weighted average common shares and common share equivalents outstanding - diluted (in shares)	10,365,306	10,295,337
Average number of potentially dilutive securities excluded from calculation (in shares)	103,756	47,260

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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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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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