Note 11 - Fair Value Measurement - Carrying Values and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Investment securities available for sale	$ 310,188	$ 270,310
Accrued interest receivable	8,197	6,498
Servicing rights on sold loans	2,776	3,014
Reported Value Measurement [Member]
Cash and cash equivalents	103,625	85,117
Investment securities available for sale	310,188	270,310
Loans held for sale	300	1,063
Loans receivable, net	1,577,186	1,612,028
FHLB stock	13,211	13,105
Accrued interest receivable	8,197	6,498
Servicing rights on sold loans	2,776	3,014
Interest rate swap derivative - securities and loans	734
FHLB Borrowings	263,500	260,000
Line of Credit	13,500	13,500
Subordinated debt, net	34,694	34,643
Accrued interest payable	145	1,223
Interest rate swap derivative - securities and loans		1,703
Reported Value Measurement [Member] \| Demand Deposits [Member]
Deposits	1,111,061	1,079,327
Reported Value Measurement [Member] \| Time Deposits [Member]
Deposits	523,347	519,774
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	103,625	85,117
Investment securities available for sale	310,188	270,310
Loans held for sale	300	1,063
Loans receivable, net	1,482,591	1,504,219
FHLB stock	13,211	13,105
Accrued interest receivable	8,197	6,498
Servicing rights on sold loans	2,776	3,014
Interest rate swap derivative - securities and loans	734
FHLB Borrowings	262,998	260,510
Line of Credit	13,597	13,589
Subordinated debt, net	39,394	35,973
Accrued interest payable	145	1,223
Interest rate swap derivative - securities and loans		1,703
Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Deposits	1,111,061	1,079,327
Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Deposits	520,551	520,033
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	103,625	85,117
Investment securities available for sale	12,447	13,885
Loans held for sale	0	0
Loans receivable, net	0	0
FHLB stock	0	0
Accrued interest receivable	0	0
Servicing rights on sold loans	0	0
Interest rate swap derivative - securities and loans	0
FHLB Borrowings	0	0
Line of Credit	0	0
Subordinated debt, net	0	0
Accrued interest payable	0	0
Interest rate swap derivative - securities and loans		0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Demand Deposits [Member]
Deposits	1,111,061	1,079,327
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Time Deposits [Member]
Deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Investment securities available for sale	288,507	249,826
Loans held for sale	300	1,063
Loans receivable, net	0	0
FHLB stock	13,211	13,105
Accrued interest receivable	8,197	6,498
Servicing rights on sold loans	0	0
Interest rate swap derivative - securities and loans	734
FHLB Borrowings	0	0
Line of Credit	0	0
Subordinated debt, net	0	0
Accrued interest payable	145	1,223
Interest rate swap derivative - securities and loans		1,703
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Demand Deposits [Member]
Deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Time Deposits [Member]
Deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Investment securities available for sale	9,234	6,599
Loans held for sale	0	0
Loans receivable, net	1,482,591	1,504,219
FHLB stock	0	0
Accrued interest receivable	0	0
Servicing rights on sold loans	2,776	3,014
Interest rate swap derivative - securities and loans	0
FHLB Borrowings	262,998	260,510
Line of Credit	13,597	13,589
Subordinated debt, net	39,394	35,973
Accrued interest payable	0	0
Interest rate swap derivative - securities and loans		0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Demand Deposits [Member]
Deposits	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Time Deposits [Member]
Deposits	$ 520,551	$ 520,033

The fair value portion of interest payable.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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