Note 13 - Fair Value Measurement - Carrying Values and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Investment securities available for sale	$ 310,860	$ 295,623
Accrued interest receivable	8,939	7,894
Sold loan servicing rights	3,584	3,793
Reported Value Measurement [Member]
Cash and cash equivalents	82,722	123,169
Investment securities available for sale	310,860	295,623
Loans held for sale	378	753
Loans receivable, net	1,714,416	1,642,518
FHLB stock	14,435	13,664
Accrued interest receivable	8,939	7,894
Sold loan servicing rights	3,584	3,793
Equity and partnership investments	14,412	13,183
FHLB Borrowings	290,000	275,000
Line of Credit	5,500	6,500
Subordinated debt, net	39,494	39,436
Accrued interest payable	2,153	3,396
Interest rate swap derivative	2,749	1,002
Interest rate swap derivative	2,749	1,002
Reported Value Measurement [Member] \| Demand Deposits [Member]
Deposits	1,066,271	1,025,854
Reported Value Measurement [Member] \| Time Deposits [Member]
Deposits	645,370	651,038
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	82,722	123,169
Investment securities available for sale	310,860	295,623
Loans held for sale	378	753
Loans receivable, net	1,580,047	1,506,130
FHLB stock	14,435	13,664
Accrued interest receivable	8,939	7,894
Sold loan servicing rights	3,584	3,793
Equity and partnership investments	14,412	13,183
FHLB Borrowings	290,119	271,284
Line of Credit	5,525	6,524
Subordinated debt, net	42,016	42,116
Accrued interest payable	2,153	3,396
Interest rate swap derivative	2,749	1,002
Interest rate swap derivative	2,749	1,002
Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Deposits	1,066,271	1,025,854
Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Deposits	647,583	648,428
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	82,722	123,169
Investment securities available for sale	6,999	7,001
Loans held for sale	0	0
Loans receivable, net	0	0
FHLB stock	0	0
Accrued interest receivable	0	0
Sold loan servicing rights	0	0
Equity and partnership investments	0	0
FHLB Borrowings	0	0
Line of Credit	0	0
Subordinated debt, net	0	0
Accrued interest payable	0	0
Interest rate swap derivative	0	0
Interest rate swap derivative	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Demand Deposits [Member]
Deposits	1,066,271	1,025,854
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	286,766	261,153
Loans held for sale	378	753
Loans receivable, net	0	0
FHLB stock	14,435	13,664
Accrued interest receivable	8,939	7,894
Sold loan servicing rights	0	0
Equity and partnership investments	1,762	0
FHLB Borrowings	0	0
Line of Credit	0	0
Subordinated debt, net	0	0
Accrued interest payable	2,153	3,396
Interest rate swap derivative	2,749	1,002
Interest rate swap derivative	2,749	1,002
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	17,095	27,469
Loans held for sale	0	0
Loans receivable, net	1,580,047	1,506,130
FHLB stock	0	0
Accrued interest receivable	0	0
Sold loan servicing rights	3,584	3,793
Equity and partnership investments	12,650	13,183
FHLB Borrowings	290,119	271,284
Line of Credit	5,525	6,524
Subordinated debt, net	42,016	42,116
Accrued interest payable	0	0
Interest rate swap derivative	0	0
Interest rate swap derivative	0	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	$ 647,583	$ 648,428

The fair value portion of interest payable.

No definition available.

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- Definition

Amount 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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- Definition

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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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 portion of investments accounted under the equity method.

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

+ References

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- Definition

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

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- Definition

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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- Definition

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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- Definition

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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