Note 9 - Derivatives and Hedging Activities (Details Textual) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Noninterest Expense, Total	$ 25,117,000	$ 22,940,000
Interest Rate Swap [Member]
Derivative Liability, Fair Value, Amount Not Offset Against Collateral, Total	800,000		$ 1,000,000.0
Derivative, Collateral, Right to Reclaim Cash	700,000		1,100,000
Derivative, Notional Amount	$ 65,855,000		33,731,000
Noninterest Expense, Total			$ 100,000