Note 12 - Net Income (Loss) Per-share - Reconciliation of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Net income (loss)	$ 766	$ (1,023)
Weighted-average shares of common stock outstanding (in shares)	15,505	15,405
Basic net income (loss) per share (in dollars per share)	$ 0.05	$ (0.07)
Plus interest expense on convertible debt
	$ 766	$ (1,023)
Dilutive options and warrants outstanding (in shares)	1,156
Effect of conversion of convertible notes (in shares)	3
Number of shares used in diluted per-share computation (in shares)	16,664	15,405
Diluted net income (loss) per share (in dollars per share)	$ 0.05	$ (0.07)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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