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Note 2 - Securities - Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Available-for-Sale, Amortized Cost	$ 299,707	$ 295,849
Securities available for sale, gross unrealized gains	610	682
Securities available for sale, gross unrealized losses	(27,332)	(26,221)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	272,985	270,310
Securities available for sale, allowance for credit losses	0	0
US States and Political Subdivisions Debt Securities [Member]
Available-for-Sale, Amortized Cost	91,924	92,148
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(12,359)	(11,896)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	79,565	80,252
Securities available for sale, allowance for credit losses	0	0
US Government Agencies Debt Securities [Member]
Available-for-Sale, Amortized Cost	11,665	11,927
Securities available for sale, gross unrealized gains	3	28
Securities available for sale, gross unrealized losses	(36)	(12)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	11,632	11,943
Securities available for sale, allowance for credit losses	0	0
Corporate Issued Asset-backed Securities [Member]
Available-for-Sale, Amortized Cost	7,670	7,963
Securities available for sale, gross unrealized gains	9	2
Securities available for sale, gross unrealized losses	(3)	(4)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	7,676	7,961
Securities available for sale, allowance for credit losses	0	0
Corporate Debt Securities [Member]
Available-for-Sale, Amortized Cost	38,525	39,772
Securities available for sale, gross unrealized gains	320	251
Securities available for sale, gross unrealized losses	(1,453)	(1,222)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	37,392	38,801
Securities available for sale, allowance for credit losses	0	0
US Small Business Administration Securities [Member]
Available-for-Sale, Amortized Cost	5,810	6,293
Securities available for sale, gross unrealized gains	22	18
Securities available for sale, gross unrealized losses	(12)	(18)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	5,820	6,293
Securities available for sale, allowance for credit losses	0	0
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Available-for-Sale, Amortized Cost	108,375	101,618
Securities available for sale, gross unrealized gains	255	379
Securities available for sale, gross unrealized losses	(10,662)	(10,341)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	97,968	91,656
Securities available for sale, allowance for credit losses	0	0
Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Available-for-Sale, Amortized Cost	35,738	36,128
Securities available for sale, gross unrealized gains	1	4
Securities available for sale, gross unrealized losses	(2,807)	(2,728)
Investment securities available for sale, at fair value (amortized cost of $299,707 and $295,849, respectively)	32,932	33,404
Securities available for sale, allowance for credit losses	$ 0	$ 0

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

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+ 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

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/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

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/1943274/2147478546/942-210-S99-1

Reference 4: 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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