Note 8 - Deposits - Public Entity Deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Collateralized by investment securities	$ 6,350	$ 8,440
U.S. govt. sponsored agency securities.
Collateralized by investment securities	3,080	3,668
Residential mortgage-backed and related securities
Collateralized by investment securities	$ 3,270	$ 4,772