Note 3 - Loans (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Financing Receivable, Unamortized Loan Cost (Fee) and Purchase Premium (Discount)	$ 1,900	$ 1,700
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	1,464,406	1,449,745	$ 1,449,950
Financing Receivable, Purchased with Credit Deterioration, Discount (Premium)	12,900
Commercial and Industrial Loans [Member]
Financing Receivable, Unamortized Purchase Premium (Discount)	3,700	4,100
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	115,202	117,944	132,396
Consumer and Other Loans [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	18,329	19,116	$ 20,774
Consumer and Other Loans [Member] \| Demand Deposit Overdrafts [Member]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	546	543
Loans Acquired Through Business Combinations [Member]
Financing Receivable, Unamortized Purchase Premium (Discount)	$ 12,900	$ 13,200

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of unamortized loan commitment, origination, and other costs (fees) and purchase premium (discount) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of unamortized purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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