Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Trade accounts receivable, allowance for doubtful accounts	$ 165	$ 141
Property, plant and equipment, accumulated depreciation	$ 8,289	$ 8,154
Capital 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, authorized (in shares)	22,000,000	22,000,000
Common stock, shares issued (in shares)	5,798,103	5,792,126
Common stock, shares outstanding (in shares)	5,798,103	5,792,126