Note 9 - Derivative Financial Instruments and Hedging Activities - Derivative Financial Instruments (Details) - Cash Flow Hedging [Member] - Interest Rate Swap [Member] $ in Thousands	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Notional amount	$ 28,500	$ 28,500
Positions	3	3
Assets	$ 0	$ 0
Liabilities	3,087	4,868
Cash collateral pledged	$ 5,750	$ 5,750

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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