Note 4 - Allowance for Credit Losses (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss	$ 14,735	$ 12,603	$ 16,400	$ 11,974
Financing Receivable, Modified, Accumulated	0	0
Financing Receivable, Modified, Subsequent Default	0	0
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	104	0
Other Liabilities [Member]
Off-Balance-Sheet, Credit Loss, Liability	590	$ 413
TDR Loans [Member]
Financing Receivable, Allowance for Credit Loss	0
Collateral Pledged [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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- Definition

Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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