CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 1,088	$ 1,146
Preferred stock, par value (in dollars per share)	$ 0.05	$ 0.05
Preferred stock, shares authorized	4,000,000	4,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.05	$ 0.05
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares outstanding	14,782,018	14,496,359
Treasury stock, shares	39,783	2,378