Note 10 - Net Income (Loss) Per Common Share - Calculation of Diluted Shares (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Basic	$ (16,380)	$ 3,425	$ 5,093	$ (14,909)
Diluted	$ (16,380)	$ 545	$ 350	$ (14,909)
Basic weighted average shares outstanding (in shares)	23,292,635	18,819,459	22,151,726	18,734,401
Diluted weighted average shares outstanding (in shares)	23,292,635	24,539,299	27,013,580	18,734,401
Basic earnings per share (in dollars per share)	$ (0.70)	$ 0.18	$ 0.23	$ (0.80)
Diluted earnings per share (in dollars per share)	$ (0.70)	$ 0.02	$ 0.01	$ (0.80)