Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accumulated depreciation	$ 26,692	$ 26,174
Accumulated amortization	$ 6,810	$ 6,671
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	40,000,000	40,000,000
Common stock, shares issued (in shares)	25,509,298	25,053,480
Common stock, shares outstanding (in shares)	24,701,159	24,592,578

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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