Note 12 - Stock Incentive Plans - Share-based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Total compensation cost for share-based payments	$ 498	$ 242
Weighted average grant-date fair value of equity instruments granted (per share) (in dollars per share)		$ 1.80
Total fair value of shares vested during the period	$ 991	$ 1,524
Unamortized share-based payments	$ 947	$ 1,156
Weighted average period to be recognized as expense (Year)	1 year	1 year 255 days