Note 4 - Securities Available for Sale - Summary of Securities Available for Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Securities available for sale, amortized cost	$ 233,478	$ 272,319
Investment securities available for sale, gross unrealized gains	120	0
Investment securities available for sale, gross unrealized losses	(18,504)	(26,300)
Securities available for sale	215,094	246,019
Mortgage Backed Securities, Issued by Us Government Sponsored Enterprises, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Securities available for sale, amortized cost	96,837	117,690
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(9,704)	(12,754)
Securities available for sale	87,133	104,936
Mortgage Backed Securities, Issued by Us Government Sponsored Enterprises, Federal Home Loan Mortgage Corporation Certificates and Obligations FHLMC [Member]
Securities available for sale, amortized cost	82,495	98,893
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(8,246)	(11,177)
Securities available for sale	74,249	87,716
Mortgage Backed Securities, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Securities available for sale, amortized cost	34	38
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(2)	(2)
Securities available for sale	32	36
Collateralized Mortgage-Backed Securities [Member]
Securities available for sale, amortized cost	179,366	216,621
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(17,952)	(23,933)
Securities available for sale	161,414	192,688
Other Marketable Securities, Us Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	54,112	54,998
Investment securities available for sale, gross unrealized gains	120	0
Investment securities available for sale, gross unrealized losses	(552)	(2,157)
Securities available for sale	53,680	52,841
Other Marketable Securities [Member]
Securities available for sale, amortized cost	54,112	55,698
Investment securities available for sale, gross unrealized gains	120	0
Investment securities available for sale, gross unrealized losses	(552)	(2,367)
Securities available for sale	$ 53,680	53,331
Other Marketable Securities, Corporate Preferred Stock [Member]
Securities available for sale, amortized cost		700
Investment securities available for sale, gross unrealized gains		0
Investment securities available for sale, gross unrealized losses		(210)
Securities available for sale		$ 490

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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+ 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 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 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
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-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 45
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-Publisher FASB
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+ References

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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
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-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

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//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 30
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-Section 45
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