Note 2 - Securities - Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Value of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Available-for-Sale, Amortized Cost	$ 348,325	$ 295,849
Securities available for sale, gross unrealized gains	366	682
Securities available for sale, gross unrealized losses	(38,503)	(26,221)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	310,188	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	91,412	92,148
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	(18,654)	(11,896)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	72,758	80,252
Securities available for sale, allowance for credit losses	0	0
US Government Agencies Debt Securities [Member]
Available-for-Sale, Amortized Cost	11,151	11,927
Securities available for sale, gross unrealized gains	19	28
Securities available for sale, gross unrealized losses	0	(12)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	11,170	11,943
Securities available for sale, allowance for credit losses	0	0
Corporate Issued Asset-backed Securities [Member]
Available-for-Sale, Amortized Cost	21,093	7,963
Securities available for sale, gross unrealized gains	7	2
Securities available for sale, gross unrealized losses	(12)	(4)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	21,088	7,961
Securities available for sale, allowance for credit losses	0	0
Corporate Debt Securities [Member]
Available-for-Sale, Amortized Cost	61,575	39,772
Securities available for sale, gross unrealized gains	286	251
Securities available for sale, gross unrealized losses	(1,670)	(1,222)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	60,191	38,801
Securities available for sale, allowance for credit losses	0	0
US Small Business Administration Securities [Member]
Available-for-Sale, Amortized Cost	4,915	6,293
Securities available for sale, gross unrealized gains	22	18
Securities available for sale, gross unrealized losses	(14)	(18)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	4,923	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	105,381	101,618
Securities available for sale, gross unrealized gains	32	379
Securities available for sale, gross unrealized losses	(14,196)	(10,341)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	91,217	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	52,798	36,128
Securities available for sale, gross unrealized gains	0	4
Securities available for sale, gross unrealized losses	(3,957)	(2,728)
Investment securities available for sale, at fair value (amortized cost of $348,325 and $295,849, respectively)	48,841	33,404
Securities available for sale, allowance for credit losses	$ 0	$ 0

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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+ 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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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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