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Note 7 - Investment and Equity Securities - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Amortized cost	$ 193,977	$ 192,998
Gross unrealized gains	91	52
Gross unrealized losses	(24,463)	(28,083)
Investment securities available for sale, at fair value	169,605	164,967
Subordinated Debt Securities [Member]
Amortized cost	34,300	32,300
Gross unrealized gains	8	3
Gross unrealized losses	(1,795)	(2,139)
Investment securities available for sale, at fair value	32,513	30,164
Taxable Municipal Bonds [Member]
Amortized cost	500	500
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Investment securities available for sale, at fair value	500	500
Nontaxable Municipal Bonds [Member]
Amortized cost	151,204	151,896
Gross unrealized gains	82	49
Gross unrealized losses	(22,027)	(25,111)
Investment securities available for sale, at fair value	129,259	126,834
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	7,973	8,302
Gross unrealized gains	1	0
Gross unrealized losses	(641)	(833)
Investment securities available for sale, at fair value	$ 7,333	$ 7,469

X

- Definition

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).

+ References

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
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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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- Definition

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))
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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

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Paragraph 1
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-SubTopic 30
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