Consolidated Balance Sheets (Parentheticals) - $ / shares shares in Thousands	Dec. 31, 2017	Dec. 31, 2016
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1,000	1,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	49,000	49,000
Common stock, shares issued (in shares)	16,316	16,370
Common stock, shares outstanding (in shares)	15,547	15,622
Treasury stock, shares (in shares)	769	748