Note C - Net Earnings (Loss) Per Share - Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net loss	$ (288)	$ (586)	$ (2,041)	$ (3,452)
Net loss per share:
Basic (in dollars per share)	$ (0.01)	$ (0.03)	$ (0.09)	$ (0.16)
Diluted (in dollars per share)	$ (0.01)	$ (0.03)	$ (0.09)	$ (0.16)
Weighted average number of shares of common stock outstanding during the period used to compute basic net earnings (loss) per share (in thousands) (in shares)	22,681	22,180	22,680	22,141
Incremental shares attributable to exercise of outstanding options, stock appreciation rights and restricted stock units (assuming proceeds would be used to purchase treasury stock) (in thousands) (in shares)
Weighted average number of shares of common stock used to compute diluted net earnings (loss) per share (in thousands) (in shares)	22,681	22,180	22,680	22,141