Note 3 - Loans Receivable (Details Textual)	12 Months Ended
Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Financing Receivable, Unamortized Loan Cost (Fee) and Purchase Premium (Discount)	$ 21,500,000	$ 19,100,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss	5,000,000	6,000,000
Financing Receivable, Nonaccrual, Interest Income	132,000	201,000
Financing Receivable, Individually Evaluated for Credit Loss	25,900,000	35,800,000
Financing Receivable, Allowance for Credit Loss, Individually Evaluated	$ 151,000	$ 2,500,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable	Interest Receivable
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Financing Receivable, Modified, Number of Contracts		2,000,000
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount		$ 17,000
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable, Individually Evaluated for Credit Loss, Still Accruing	$ 4,500,000
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Extended Maturity and Interest Rate Reduction [Member]
Financing Receivable, Modified, Number of Contracts	3
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount	$ 5,500,000
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Individually Evaluated for Credit Loss, Still Accruing		6,400,000
Commercial Real Estate Portfolio Segment [Member] \| Payment Deferral [Member]
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount	4,100,000	6,400,000
Valuation Technique, Discounted Cash Flow [Member]
Financing Receivable, Individually Evaluated for Credit Loss	303,000	2,500,000
Valuation Technique, Underlying Value of Collateral [Member]
Financing Receivable, Individually Evaluated for Credit Loss	$ 25,600,000	$ 33,200,000

The amount of financing receivable individually evaluated for credit loss that is still accruing.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-5

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- Definition

Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable.

+ References

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- Definition

Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

+ References

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- Definition

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

+ References

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

Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss.

+ References

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

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- Definition

Amount of unamortized loan commitment, origination, and other costs (fees) and purchase premium (discount) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

+ References

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