Note 7 - Securities Available for Sale - Summary of Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Securities available for sale, amortized cost	$ 263,148	$ 272,319
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(23,455)	(26,300)
Securities available for sale	239,693	246,019
Mortgage Backed Securities, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Securities available for sale, amortized cost	112,599	117,690
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(11,599)	(12,754)
Securities available for sale	101,000	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	94,813	98,893
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(10,013)	(11,177)
Securities available for sale	84,800	87,716
Mortgage Backed Securities, Issued by Us Government Sponsored Enterprises, Federal National Mortgage Association Certificates and Obligations FNMA [Member]
Securities available for sale, amortized cost	38	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	36	36
Collateralized Mortgage-Backed Securities [Member]
Securities available for sale, amortized cost	207,450	216,621
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(21,614)	(23,933)
Securities available for sale	185,836	192,688
Other Marketable Securities, Us Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	54,998	54,998
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(1,596)	(2,157)
Securities available for sale	53,402	52,841
Other Marketable Securities, Corporate Preferred Stock [Member]
Securities available for sale, amortized cost	700	700
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(245)	(210)
Securities available for sale	455	490
Other Marketable Securities [Member]
Securities available for sale, amortized cost	55,698	55,698
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(1,841)	(2,367)
Securities available for sale	$ 53,857	$ 53,331

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 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
-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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+ 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
-Name Accounting Standards Codification
-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
-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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