Note 6 - Credit Quality Indicators (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Risk Rating Threshold	$ 3,000
Financing Receivable, Held-for-Sale	28,426	$ 30,171
Other Real Estate	52	52
Repossessed Assets	172	631
Financing Receivable, before Allowance for Credit Loss	3,251,391	3,268,346
Financing Receivable, Allowance for Credit Loss	35,549	35,863	$ 33,159	$ 34,440
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	(314,000)
Unfunded Loan Commitment [Member]
Financing Receivable, before Allowance for Credit Loss	683,000	692,000
Financing Receivable, Allowance for Credit Loss	1,340	1,560
Increase (Decrease) in Notes Receivables	(9,000)
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	(226)
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	19,480	19,259	17,481	18,150
Commercial Real Estate Portfolio Segment [Member] \| Farmland [Member]
Financing Receivable, Held-for-Sale	1	3
Financing Receivable, before Allowance for Credit Loss	214,028	206,600
Commercial Real Estate Portfolio Segment [Member] \| Nonowner Occupied [Member]
Financing Receivable, Held-for-Sale	25,555	26,890
Financing Receivable, before Allowance for Credit Loss	695,112	695,284
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss	4,383	4,628	$ 4,543	$ 5,087
Commercial Portfolio Segment [Member] \| Agricultural [Member]
Financing Receivable, Held-for-Sale	117	117
Financing Receivable, before Allowance for Credit Loss	54,358	56,429
Substandard [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Farmland [Member]
Financing Receivable, Held-for-Sale	1,680
Financing Receivable, before Allowance for Credit Loss	539	2,252
Substandard [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Nonowner Occupied [Member]
Financing Receivable, Held-for-Sale		1,630
Financing Receivable, before Allowance for Credit Loss	33,027	33,781
Substandard [Member] \| Commercial Portfolio Segment [Member] \| Agricultural [Member]
Financing Receivable, Held-for-Sale	163
Financing Receivable, before Allowance for Credit Loss	$ 238	$ 363

Represents the threshold for financing receivables to be evaluated for risk.

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- Definition

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

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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The increase (decrease) during the reporting period of the amounts due from borrowers for outstanding secured or unsecured loans evidenced by a note.

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

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- Definition

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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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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