Note 4 - Loans, Allowance for Credit Losses and Other Real Estate Owned (Details Textual) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Nonaccrual	$ 1,165		$ 1,474
Financing Receivable, Modified, Commitment to Lend	0		0
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount	0	$ 0
Financing Receivable, Held-for-Sale	0		0
Other Real Estate	0		0
Mortgage Loans in Process of Foreclosure, Amount	0		0
Commercial Real Estate Portfolio Segment [Member]
Nonaccrual	$ 380		$ 379
Number of Collateral-dependent Loans	5		5
Collateral-dependent Loans, Balance	$ 6,900		$ 7,000
Originated four years before, writeoff	0		0
Commercial Portfolio Segment [Member]
Nonaccrual	$ 785		$ 1,095
Number of Collateral-dependent Loans	1		1
Collateral-dependent Loans, Balance	$ 156		$ 182
Originated four years before, writeoff	0		1,559
Consumer Portfolio Segment [Member]
Nonaccrual	0		0
Collateral-dependent Loans, Balance	245		295
Originated four years before, writeoff	220		679
Nonperforming Financial Instruments [Member]
Financing Receivable, Excluding Accrued Interest, Nonaccrual, Allowance	$ 78		$ 388
Financing Receivable, Nonaccrual, Number of Loans	1		1
Nonaccrual	$ 686		$ 388

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
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Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

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Amount, excluding accrued interest, of writeoff of financing receivable originated four years before current fiscal year. Excludes net investment in lease.

+ References

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Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Represents the balance of collateral-dependent loans as of the specified date. A loan is considered collateral-dependent when the borrower is experiencing financial difficult and repayment is expected to be provided substantially through the operation or sale of the collateral.

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No definition available.

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Amount of allowance, excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

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Number of loans on nonaccrual.

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Represents the number of collateral-dependent loans as of the specified date.

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