Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Accounts receivable-trade, net allowance for doubtful accounts	$ 3,548	$ 2,404
Other intangible, accumulated amortization	$ 709,289	$ 708,845
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0024	$ 0.0024
Common stock, shares authorized (in shares)	25,000,000	25,000,000
Common stock, shares issued (in shares)	11,318,331	11,309,326
Common stock, shares outstanding (in shares)	9,275,501	9,266,496
Treasury stock, shares (in shares)	2,042,830	2,042,830