Note 6 - Core Deposit Intangible Asset, Net (Details Textual) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Core Deposits, Gross	$ 17,500,000	$ 17,500,000
Finite-Lived Intangible Assets, Accumulated Amortization	16,100,000	15,100,000
Finite-Lived Intangible Assets, Net, Ending Balance	$ 1,351,000	$ 2,436,000