CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Property and equipment, accumulated depreciation	$ 6,287	$ 5,673
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	10,196,635	9,980,827
Common stock, shares outstanding	9,018,436	8,899,587
Treasury stock, shares	1,178,199	1,081,240