Note 4 - Allowance for Credit Losses - Troubled Debt Restructurings (Details) - Real Estate 1 [Member] $ in Thousands	6 Months Ended
Jun. 30, 2026 USD ($)
Payment Deferral [Member]
Modification amount	$ 78
Modification percent	0.07%
Payment Deferral [Member] \| Commercial and Industrial Loans [Member]
Modification amount	$ 78
Modification percent	0.07%
Extended Maturity [Member]
Modification percent	0.09%
Modification amount	$ 105
Extended Maturity [Member] \| Commercial and Industrial Loans [Member]
Modification percent	0.09%
Modification amount	$ 105

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
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-Publisher FASB
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- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

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Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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