Note 15 - Stock Repurchase Plan (Details Textual) - USD ($) $ in Thousands	12 Months Ended	38 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Oct. 27, 2015
Stock Repurchase Program, Authorized Amount				$ 5,000
Stock Repurchased and Retired During Period, Shares	0	13,883	297,020
Stock Repurchased and Retired During Period, Value	$ 62	$ 62	$ 1,195

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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