Note 11 - Earnings (Loss) Per Share - Computation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
EARNINGS PER SHARE
Net income (loss)	$ 7,035	$ 9,942	$ 4,143	$ (4,776)	$ 2,652	$ 1,962	$ 21,120	$ (162)
Weighted average shares used to compute basic EPS (in shares)	44,109			42,647			43,915	42,373
Dilutive effect of stock-based awards (in shares)	356						81
Weighted average shares used to compute diluted EPS (in shares)	44,465			42,647			43,996	42,373
Basic (in dollars per share)	$ 0.16			$ (0.11)			$ 0.48	$ 0.00
Diluted (in dollars per share)	$ 0.16			$ (0.11)			$ 0.48	$ 0.00
Antidilutive shares							937,424