Note 15 - Derivatives and Hedging Activities (Details Textual) Pure in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Noninterest Expense, Total	$ 98,520,000	$ 89,280,000	$ 86,170,000
Interest Rate Swap [Member]
Noninterest Expense, Total	100,000
Derivative, Number of Instruments Held, Total		0
Derivative Liability, Fair Value, Amount Not Offset Against Collateral, Total	1,000,000.0
Derivative, Collateral, Right to Reclaim Cash	1,100,000
Derivative, Notional Amount	$ 33,731,000