Note 2 - Summary of Significant Accounting Policies - Components of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Cash and cash equivalents	$ 3,931	$ 7,504
Restricted cash included in other assets	155	475
Total cash, cash equivalents, and restricted cash in the condensed consolidated balance sheets	$ 4,086	$ 7,979	$ 10,769	$ 12,427