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Note 6 - Investment and Equity Securities- Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands		Sep. 30, 2025	Dec. 31, 2024
Amortized cost	[1]	$ 179,747	$ 191,211
Gross unrealized gains		152	72
Gross unrealized losses		(24,044)	(25,481)
Investment securities available for sale, at fair value		155,855	165,802
Subordinated Debt Securities [Member]
Amortized cost	[1]	24,500	34,300
Gross unrealized gains		85	67
Gross unrealized losses		(1,013)	(1,898)
Investment securities available for sale, at fair value		23,572	32,469
Nontaxable Municipal Bonds [Member]
Amortized cost	[1]	146,851	147,767
Gross unrealized gains		21	4
Gross unrealized losses		(22,499)	(22,805)
Investment securities available for sale, at fair value		124,373	124,966
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Amortized cost	[1]	8,396	9,144
Gross unrealized gains		46	1
Gross unrealized losses		(532)	(778)
Investment securities available for sale, at fair value		$ 7,910	$ 8,367
[1] Accrued interest of $1.5 million is excluded from amortized cost and presented in "accrued interest receivable and other assets" on the Consolidated Balance Sheet.

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
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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- Definition

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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- Definition

Amortized cost excluding accrued interest, before 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/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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- Definition

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/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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