Note 6 - Available-for-Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	$ 460,418	$ 490,182
Investment securities available-for-sale, debt securities gross unrealized holding gains	13	5
Investment securities available-for-sale, debt securities gross unrealized holding losses	(88,101)	(84,252)
Investment securities available-for-sale, debt securities gross unrealized fair value hedge gains (losses)	6,015	(1,749)
Investment securities available-for-sale, debt securities amortized cost	542,491	576,178
US Treasury Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	6,449	6,451
Investment securities available-for-sale, debt securities gross unrealized holding gains		3
Investment securities available-for-sale, debt securities gross unrealized holding losses	(1)
Investment securities available-for-sale, debt securities amortized cost	6,450	6,448
US Government Agencies Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	65,633	74,122
Investment securities available-for-sale, debt securities gross unrealized holding losses	(10,322)	(10,828)
Investment securities available-for-sale, debt securities amortized cost	75,955	84,950
US States and Political Subdivisions Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	86,693	89,189
Investment securities available-for-sale, debt securities gross unrealized holding losses	(20,809)	(18,714)
Investment securities available-for-sale, debt securities gross unrealized fair value hedge gains (losses)	1,761	(445)
Investment securities available-for-sale, debt securities amortized cost	105,741	108,348
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	211,783	224,238
Investment securities available-for-sale, debt securities gross unrealized holding losses	(39,741)	(37,831)
Investment securities available-for-sale, debt securities gross unrealized fair value hedge gains (losses)	4,254	(1,304)
Investment securities available-for-sale, debt securities amortized cost	247,270	263,373
Collateralized Mortgage Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	83,480	89,973
Investment securities available-for-sale, debt securities gross unrealized holding losses	(16,868)	(16,383)
Investment securities available-for-sale, debt securities amortized cost	100,348	106,356
Corporate Debt Securities and Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	6,380	6,209
Investment securities available-for-sale, debt securities gross unrealized holding gains	13	2
Investment securities available-for-sale, debt securities gross unrealized holding losses	(360)	(496)
Investment securities available-for-sale, debt securities amortized cost	$ 6,727	$ 6,703

Available for sale debt securities accumulated gross unrealized fair value hedge gain (loss) before tax.

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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