Note 3 - Loans and Allowance for Credit Losses (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Financing Receivable, Allowance for Credit Loss	$ 16,867	$ 20,284	$ 23,514	$ 23,854
Loans and Leases Receivable, Nonaccrual, Commitment to Lend	0	0
Financing Receivable, Modified in Period, Amount	0	0
Financing Receivable, Held-for-Sale	0	0
Other Real Estate	0	0
Mortgage Loans in Process of Foreclosure, Amount	0	0
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	$ 5,925	$ 5,888	6,529	5,660
Number of Collateral-dependent Loans	9	5
Collateral-dependent Loans, Balance	$ 10,900	$ 8,100
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	6,455	8,076	$ 9,972	$ 8,936
Collateral-dependent Loans, Balance	377	625
Nonperforming Financial Instruments [Member]
Financing Receivable, Allowance for Credit Loss	$ 0	$ 0

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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