CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts	$ 68	$ 40
Par value of common stock (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	75,000	75,000
Common stock, shares issued	23,789	23,786
Common stock, shares outstanding	23,789	23,786
Treasury stock, shares reserved	1,250	1,250
Series A
Par value of convertible preferred stock (in dollars per share)	$ 0	$ 0
Convertible preferred stock, shares authorized	1	1
Convertible preferred stock, shares reserved	1	1
Convertible preferred stock, shares issued	1	1
Convertible preferred stock, shares outstanding	1	1
Series B-2
Par value of convertible preferred stock (in dollars per share)	$ 0	$ 0
Convertible preferred stock, shares authorized	39	39
Convertible preferred stock, shares reserved	39	39
Convertible preferred stock, shares issued	12	12
Convertible preferred stock, shares outstanding	12	12