Note 4 - Debt Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	$ 546,525	$ 692,360
Investment securities available-for-sale, debt securities gross unrealized holding gains	2	3,568
Investment securities available-for-sale, debt securities gross unrealized holding losses	(102,694)	(8,302)
Investment securities available-for-sale, debt securities amortized cost	649,217	697,094
US Treasury Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	301
Investment securities available-for-sale, debt securities gross unrealized holding gains	2
Investment securities available-for-sale, debt securities amortized cost	299
US Government Agencies Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	86,709	97,499
Investment securities available-for-sale, debt securities gross unrealized holding gains		2
Investment securities available-for-sale, debt securities gross unrealized holding losses	(15,233)	(2,435)
Investment securities available-for-sale, debt securities amortized cost	101,942	99,932
US States and Political Subdivisions Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	95,367	131,035
Investment securities available-for-sale, debt securities gross unrealized holding gains		1,716
Investment securities available-for-sale, debt securities gross unrealized holding losses	(23,494)	(1,053)
Investment securities available-for-sale, debt securities amortized cost	118,861	130,372
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	256,161	329,938
Investment securities available-for-sale, debt securities gross unrealized holding gains		1,273
Investment securities available-for-sale, debt securities gross unrealized holding losses	(45,303)	(3,158)
Investment securities available-for-sale, debt securities amortized cost	301,464	331,823
Collateralized Mortgage Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	101,672	127,012
Investment securities available-for-sale, debt securities gross unrealized holding gains		398
Investment securities available-for-sale, debt securities gross unrealized holding losses	(18,338)	(1,648)
Investment securities available-for-sale, debt securities amortized cost	120,010	128,262
Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Investment securities available-for-sale, debt securities	6,315	6,876
Investment securities available-for-sale, debt securities gross unrealized holding gains		179
Investment securities available-for-sale, debt securities gross unrealized holding losses	(326)	(8)
Investment securities available-for-sale, debt securities amortized cost	$ 6,641	$ 6,705

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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-SubTopic 10
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