Note 2 - Securities - Amortized Cost and Estimated Fair Value of Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Securities available for sale, amortized cost	$ 333,950	$ 375,183
Investment securities available for sale, at fair value	295,623	326,569
Collateralized Mortgage-Backed Securities [Member]
Due within one year, amortized cost	25,279	13,762
Due within one year, estimated fair value	25,017	13,490
Due after one through five years, amortized cost	16,622	28,890
Due after one through five years, estimated fair value	16,029	27,808
Due after five through ten years, amortized cost	8,874	13,436
Due after five through ten years, estimated fair value	8,197	12,165
Due after ten years, amortized cost	106,445	133,981
Due after ten years, estimated fair value	90,097	115,491
Securities available for sale, amortized cost	157,220	190,069
Investment securities available for sale, at fair value	139,340	168,954
Investment Securities, Excluding Mortgage Backed Securities [Member]
Due within one year, amortized cost	300	0
Due within one year, estimated fair value	300	0
Due after one through five years, amortized cost	18,187	20,700
Due after one through five years, estimated fair value	17,384	18,957
Due after five through ten years, amortized cost	57,328	64,211
Due after five through ten years, estimated fair value	50,768	57,523
Due after ten years, amortized cost	100,915	100,203
Due after ten years, estimated fair value	87,831	81,135
Securities available for sale, amortized cost	176,730	185,114
Investment securities available for sale, at fair value	$ 156,283	$ 157,615

Amortized cost of 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 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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