Note 8 - Earnings Per Share - Calculation of Basic and Diluted Weighted Average Common Shares (Details) - shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Weighted average common shares outstanding basic earnings per share (in shares)	6,562,141	6,495,597
Effect of potential common share issuance:
Stock options (in shares)
Weighted average common shares outstanding
Diluted earnings per share (in shares)	6,562,141	6,495,597

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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