Note 5 - Loss Per Common Share - Net Income Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Notes To Financial Statements [Abstract]
Net Income (Loss)	$ (22,415)	$ (23,526)	$ (41,282)	$ (32,896)
Preferred stock dividends	(138)	(138)	(414)	(414)
Net loss applicable to common stockholders	$ (22,553)	$ (23,664)	$ (41,696)	$ (33,310)
Basic weighted average common shares	607,896,000	554,531,000	604,028,000	544,000,000
Diluted weighted average common shares	607,896,000	554,531,000	604,028,000	544,000,000
Basic loss per common share	$ (0.04)	$ (0.04)	$ (0.07)	$ (0.06)
Diluted loss per common share	$ (0.04)	$ (0.04)	$ (0.07)	$ (0.06)