CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 141	$ 98
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	28,345,525	28,288,764
Common stock, shares outstanding (in shares)	27,075,962	26,932,169
Treasury stock, common shares (in shares)	1,269,563	1,356,595