Note 9 - Fair Value Measurement - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 484,686	$ 437,735
Reported Value Measurement [Member]
Cash and cash equivalents	87,279	82,018
Debt Securities, Available-for-Sale, Excluding Accrued Interest	484,686	437,735
Loans, net	1,480,415	1,005,375
FHLB stock	8,804	6,234
FRB Stock	3,155	1,380
Deposits	1,819,536	1,371,101
Repurchase agreements	93,863	22,073
Borrowings	26,705	15,000
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	87,279	82,018
Debt Securities, Available-for-Sale, Excluding Accrued Interest	484,686	437,735
Loans, net	1,444,023	981,114
FHLB stock	8,804	6,234
FRB Stock	3,155	1,380
Deposits	1,818,789	1,371,073
Repurchase agreements	93,863	22,073
Borrowings	25,986	13,967
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	87,279	82,018
Loans, net	0
FHLB stock	0
FRB Stock	0
Deposits	1,604,947	1,276,912
Repurchase agreements	0
Borrowings	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	484,686	437,735
Loans, net	0
FHLB stock	8,804	6,234
FRB Stock	3,155	1,380
Deposits	0
Repurchase agreements	93,863	22,073
Borrowings	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0
Loans, net	1,444,023	981,114
FHLB stock	0
FRB Stock	0
Deposits	213,842	94,161
Repurchase agreements	0
Borrowings	$ 25,986	$ 13,967

Fair value portion of investments in Federal Reserve Bank stock.

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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 debt instrument payable, including, but not limited to, notes payable and loans payable.

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

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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 portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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