Note 3 - Securities - Amortized Cost and Estimated Fair Values of Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Available-for-sale securities, amortized cost	$ 587,131	$ 570,040
Available-for-sale securities, gross unrealized gains	1,062	1,683
Available-for-sale securities, gross unrealized losses	(33,146)	(28,191)
Available-for-sale securities, fair market value	555,047	543,532
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized cost	117,652	104,672
Available-for-sale securities, gross unrealized gains	220	472
Available-for-sale securities, gross unrealized losses	(4,080)	(3,607)
Available-for-sale securities, fair market value	113,792	101,537
Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized cost	36,799	34,977
Available-for-sale securities, gross unrealized gains	109	140
Available-for-sale securities, gross unrealized losses	(386)	(324)
Available-for-sale securities, fair market value	36,522	34,793
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	368,821	359,902
Available-for-sale securities, gross unrealized gains	728	1,012
Available-for-sale securities, gross unrealized losses	(26,811)	(22,446)
Available-for-sale securities, fair market value	342,738	338,468
SBA Pool [Member]
Available-for-sale securities, amortized cost	527	561
Available-for-sale securities, gross unrealized gains	0	1
Available-for-sale securities, gross unrealized losses	(3)	(3)
Available-for-sale securities, fair market value	524	559
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	36,500	41,500
Available-for-sale securities, gross unrealized gains	2	21
Available-for-sale securities, gross unrealized losses	(1,178)	(1,109)
Available-for-sale securities, fair market value	35,324	40,412
Asset-Backed Securities [Member]
Available-for-sale securities, amortized cost	26,832	28,428
Available-for-sale securities, gross unrealized gains	3	37
Available-for-sale securities, gross unrealized losses	(688)	(702)
Available-for-sale securities, fair market value	$ 26,147	$ 27,763

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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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 30
-Name Accounting Standards Codification
-Section 45
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-Publisher FASB
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