Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	12,979,414	12,891,317
Treasury stock, shares	840,202	384,220