Note 5 - Derivatives - Schedule of Hedging Relationship (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Total amounts presented on the Consolidated Statements of Income	$ 15,806	$ 14,534
Interest and dividends on investment securities, cash and cash equivalents, and certificates of deposit at other financial institutions	3,485	3,883
Reclassification adjustment for realized gain, net included in net income	(871)	(1,722)
Interest Expense [Member]
Net interest income recognized on cash flows of derivatives designated as hedging instruments	0	0
Interest Income [Member]
Net interest income recognized on cash flows of derivatives designated as hedging instruments	297	418
Designated as Hedging Instrument [Member] \| Securities Investment [Member] \| Interest Rate Swap [Member] \| Interest Expense [Member]
Net gains (losses) on fair value hedging relationships: Interest rate swaps – securities, Recognized on hedged items	0	0
Recognized on derivatives designated as hedging instruments	0	0
Net income recognized on fair value hedges	0	0
Designated as Hedging Instrument [Member] \| Securities Investment [Member] \| Interest Rate Swap [Member] \| Interest Income [Member]
Net gains (losses) on fair value hedging relationships: Interest rate swaps – securities, Recognized on hedged items	392	(1,225)
Recognized on derivatives designated as hedging instruments	(392)	1,225
Net income recognized on fair value hedges	297	418
Designated as Hedging Instrument [Member] \| Brokered Deposits and Borrowings [Member] \| Interest Rate Swap [Member] \| Interest Expense [Member]
Reclassification adjustment for realized gain, net included in net income	574	1,722
Net income recognized on cash flow hedges	574	1,722
Designated as Hedging Instrument [Member] \| Brokered Deposits and Borrowings [Member] \| Interest Rate Swap [Member] \| Interest Income [Member]
Reclassification adjustment for realized gain, net included in net income	0	0
Net income recognized on cash flow hedges	0	0
Designated as Hedging Instrument [Member] \| Fair Value Hedging And Cash Flow Hedging [Member]
Total amounts presented on the Consolidated Statements of Income	15,321	12,882
Interest and dividends on investment securities, cash and cash equivalents, and certificates of deposit at other financial institutions	$ 3,485	$ 3,883

The amount of net interest income (expense) recognized on cash flow of derivatives designated as hedging instruments.

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of gain (loss) on derivative instrument designated and qualifying as fair value hedge included in assessment of hedge effectiveness, recognized in earnings.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount of interest expense classified as operating.

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Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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