Note 6 - Earnings Per Share - Computation of Basic and Diluted Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net loss	$ (16,797)	$ (10,474)
Basic (in shares)	20,208,383	19,863,090
Diluted (in shares)	20,208,383	19,863,090
Basic (in dollars per share)	$ (0.83)	$ (0.53)
Diluted (in dollars per share)	$ (0.83)	$ (0.53)