Note 1 - Significant Accounting Policies and Recent Accounting Pronouncements (Details Textual) - USD ($) $ / shares in Thousands, $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Impairment, Long-Lived Asset, Held-for-Use, Total	$ 0	$ 0
Earnings Per Share, Diluted, Total (in dollars per share)	$ 0	$ 0
Payments of Ordinary Dividends, Common Stock	$ 0	$ 0