Note 3 - Securities - Amortized Cost and Estimated Fair Values of Debt Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Available-for-sale securities, amortized cost	$ 545,803	$ 560,143
Available-for-sale securities, gross unrealized gains	554	992
Available-for-sale securities, gross unrealized losses	(43,010)	(34,639)
Available-for-sale securities, fair market value	503,347	526,496
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized cost	85,244	92,659
Available-for-sale securities, gross unrealized gains	39	20
Available-for-sale securities, gross unrealized losses	(4,293)	(5,605)
Available-for-sale securities, fair market value	80,990	87,074
Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized cost	26,052	29,105
Available-for-sale securities, gross unrealized gains	112	0
Available-for-sale securities, gross unrealized losses	(437)	(606)
Available-for-sale securities, fair market value	25,727	28,499
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	346,153	347,051
Available-for-sale securities, gross unrealized gains	319	900
Available-for-sale securities, gross unrealized losses	(35,881)	(25,459)
Available-for-sale securities, fair market value	310,591	322,492
SBA Pool [Member]
Available-for-sale securities, amortized cost	765	882
Available-for-sale securities, gross unrealized gains	1	0
Available-for-sale securities, gross unrealized losses	(3)	(3)
Available-for-sale securities, fair market value	763	879
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	43,500	43,500
Available-for-sale securities, gross unrealized gains	12	6
Available-for-sale securities, gross unrealized losses	(1,787)	(2,294)
Available-for-sale securities, fair market value	41,725	41,212
Asset-Backed Securities [Member]
Available-for-sale securities, amortized cost	44,089	46,946
Available-for-sale securities, gross unrealized gains	71	66
Available-for-sale securities, gross unrealized losses	(609)	(672)
Available-for-sale securities, fair market value	$ 43,551	$ 46,340

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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- Definition

Amount, before tax, of unrealized loss 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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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Amortized cost excluding accrued interest, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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Amount excluding accrued interest, of 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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