Note 10 - Fair Value of Financial Instruments - Estimated Fair Value and Carrying Amounts of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	$ 53,733	$ 62,962
FHLB stock	2,734	2,650
FRB stock	4,131	4,131
Loans receivable, gross	1,505,005	1,493,348
Mortgage servicing rights	19,747	20,302
Time certificates of deposit	471,506	461,201
FHLB advances and other borrowings	27,062	38,447
Other long-term debt	44,273	43,905
Federal Funds Purchased		105
Reported Value Measurement [Member]
Cash and cash equivalents	53,733	62,962
FHLB stock	2,734	2,650
FRB stock	4,131	4,131
Loans receivable, gross	1,519,286	1,519,019
Mortgage servicing rights	14,909	15,043
Time certificates of deposit	472,783	462,172
FHLB advances and other borrowings	26,667	37,917
Other long-term debt	45,155	45,155
Federal Funds Purchased		105
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	53,733	62,962
FHLB stock	0	0
FRB stock	0	0
Loans receivable, gross	0	0
Mortgage servicing rights	0	0
Time certificates of deposit	0	0
FHLB advances and other borrowings	0	0
Other long-term debt	0	0
Federal Funds Purchased		0
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	0	0
FHLB stock	2,734	2,650
FRB stock	4,131	4,131
Loans receivable, gross	0	0
Mortgage servicing rights	0	0
Time certificates of deposit	0	0
FHLB advances and other borrowings	0	0
Other long-term debt	0	0
Federal Funds Purchased		0
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	0	0
FHLB stock	0	0
FRB stock	0	0
Loans receivable, gross	1,505,005	1,493,348
Mortgage servicing rights	19,747	20,302
Time certificates of deposit	471,506	461,201
FHLB advances and other borrowings	27,062	38,447
Other long-term debt	$ 44,273	43,905
Federal Funds Purchased		$ 105

The fair value portion of borrowing from the Federal Home Loan Bank and other borrowings.

No definition available.

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- Definition

Fair value portion of investments in Federal Reserve Bank stock.

+ References

No definition available.

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- Definition

The fair value portion of time certificates of deposit held by the entity.

+ References

No definition available.

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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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- Definition

Fair value portion of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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- Definition

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

+ References

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- Definition

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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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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- Definition

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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