Note 9 - Derivative Financial Instruments and Hedging Activities - Derivative Financial Instruments (Details) - Cash Flow Hedging [Member] - Interest Rate Swap [Member] $ in Thousands	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Notional amount	$ 28,500	$ 28,500
Positions	3	3
Assets	$ 0	$ 0
Liabilities	3,265	4,868
Cash collateral pledged	$ 4,050	$ 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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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Nominal or face amount used to calculate payment on derivative.

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The number of derivative instruments of a particular group held by the entity.

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