Note 10 - Loans and Allowance for Credit Losses - Modified Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Modified, percentage	0.01%	0.00%	0.05%	0.02%
Principal Forgiveness [Member]
Modified	$ 0	$ 0	$ 0	$ 0
Payment Deferral [Member]
Modified	0	0	0	0
Extended Maturity [Member]
Modified	28	14	793	270
Extended Maturity and Payment Deferral [Member]
Modified	33		33
Extended Maturity and Interest Rate Reduction [Member]
Modified	$ 254	0	$ 483	219
Extended Maturity and Principal Forgiveness [Member]
Modified		$ 0		$ 0
Other Commercial [Member]
Modified, percentage	0.18%	0.01%	0.73%	0.26%
Principal forgiveness	$ 0	$ 0	$ 0	$ 0
Weighted average interest rate reduction	0.50%	0.31%	0.50%	0.31%
Weighted average term extension (Year)	6 years 1 month 6 days	7 years 5 months 23 days	3 years 8 months 26 days	7 years 3 months 7 days
Other Commercial [Member] \| Principal Forgiveness [Member]
Modified	$ 0	$ 0	$ 0	$ 0
Other Commercial [Member] \| Payment Deferral [Member]
Modified	0	0	0	0
Other Commercial [Member] \| Extended Maturity [Member]
Modified	28	14	793	270
Other Commercial [Member] \| Extended Maturity and Payment Deferral [Member]
Modified	33		33
Other Commercial [Member] \| Extended Maturity and Interest Rate Reduction [Member]
Modified	$ 254	0	$ 483	219
Other Commercial [Member] \| Extended Maturity and Principal Forgiveness [Member]
Modified		$ 0		$ 0

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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-Topic 310
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