Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Trade accounts receivable, allowance for doubtful accounts	$ 149	$ 180
Property, plant and equipment, accumulated depreciation	$ 9,078	$ 8,537
Captial stock, authorized shares (in shares)	3,000,000	3,000,000
Capital stock, shares issued (in shares)	0	0
Capital stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized (in shares)	22,000,000	22,000,000
Common stock, shares issued (in shares)	5,867,127	5,854,413
Common stock, shares outstanding (in shares)	5,867,127	5,854,413