Note 5 - Fair Value of Financial Instruments - Estimated Fair Value of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Securities available for sale	$ 206,609	$ 215,094
Reported Value Measurement [Member]
Cash and cash equivalents	50,230	11,151
Securities available for sale	206,609	215,094
Equity securities	394	382
Loans held for sale	4,146	1,006
Loans receivable, net	856,560	845,692
Federal Home Loan Bank stock	665	1,252
Accrued interest receivable	3,674	3,553
Mortgage servicing assets	2,631	2,709
Deposits	1,030,918	976,793
FHLB advances and other borrowings	0	13,200
Accrued interest payable	3,730	2,399
Commitments to extend credit	(18)	7
Commitments to sell loans	(7)	(17)
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	50,230	11,151
Securities available for sale	206,609	215,094
Equity securities	394	382
Loans held for sale	4,146	1,006
Loans receivable, net	792,017	778,952
Federal Home Loan Bank stock	665	1,252
Accrued interest receivable	3,674	3,553
Mortgage servicing assets	6,536	6,539
Deposits	1,029,689	975,963
FHLB advances and other borrowings	0	13,200
Accrued interest payable	3,730	2,399
Commitments to extend credit	(18)	7
Commitments to sell loans	(7)	(17)
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	50,230
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	206,609
Equity securities	394
Loans held for sale	4,146
Loans receivable, net	792,017
Federal Home Loan Bank stock	665
Accrued interest receivable	3,674
Mortgage servicing assets
Deposits	1,029,689
FHLB advances and other borrowings	0
Accrued interest payable	3,730
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Mortgage servicing assets	6,536
Portion at Other than Fair Value Measurement [Member]
Commitments to extend credit	159,183	167,447
Commitments to sell loans	$ 9,376	$ 3,078

Fair value portion of accrued interest payable.

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Fair value portion of accrued interest receivable.

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No definition available.

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The face amount of financial liabilities related to commitments to sell, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

No definition available.

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The fair value portion of mortgage loan commitments assets (liabilities).

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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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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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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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

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

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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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