Note 6 - Net Income Per Share - Calculation of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net income	$ 517	$ 2,061
Basic weighted-average shares outstanding (in shares)	31,991	31,168
Effect of dilutive options and restricted stock (in shares)	1,603	586
Diluted weighted average shares outstanding (in shares)	33,594	31,754
Net income per share - Basic (in dollars per share)	$ 0.02	$ 0.07
Net income per share - Diluted (in dollars per share)	$ 0.02	$ 0.07