Note 9 - Derivatives and Hedging Activities (Details Textual) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Noninterest Expense, Total	$ 26,210,000	$ 26,423,000	$ 77,519,000	$ 72,579,000
Interest Rate Swap [Member]
Noninterest Expense, Total			200,000		$ 100,000
Derivative Liability, Fair Value, Amount Not Offset Against Collateral, Total	5,300,000		5,300,000		1,000,000.0
Derivative, Collateral, Right to Reclaim Cash	4,600,000		4,600,000		1,100,000
Derivative, Notional Amount	$ 214,368,000		$ 214,368,000		$ 33,731,000