Note 11 - Fair Value Measurements - Carrying Amount and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Servicing Asset at Amortized Cost, Fair Value	$ 1,500	$ 1,300
Advance payments by borrowers for taxes	18,772	2,996
Reported Value Measurement [Member]
Cash and cash equivalents	38,201	71,107
Loans receivable	1,683,881	1,675,552
FHLB stock	19,226	19,804
Accrued interest receivable	8,151	8,331
Servicing Asset at Amortized Cost, Fair Value	1,142	1,030
Deposits	1,420,981	1,437,272
Advance payments by borrowers for taxes	18,772	2,996
Borrowings	412,000	412,258
Accrued interest payable	4,107	3,558
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	38,201	71,107
Loans receivable	1,661,155	1,632,248
FHLB stock	19,226	19,804
Accrued interest receivable	8,151	8,331
Servicing Asset at Amortized Cost, Fair Value	1,533	1,294
Deposits	1,420,692	1,436,939
Advance payments by borrowers for taxes	18,772	2,996
Borrowings	409,621	408,434
Accrued interest payable	4,107	3,558
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	38,201	71,107
Loans receivable	0	0
FHLB stock	19,226	19,804
Accrued interest receivable	8,151	8,331
Servicing Asset at Amortized Cost, Fair Value	0	0
Deposits	525,553	504,626
Advance payments by borrowers for taxes	18,772	2,996
Borrowings	0	0
Accrued interest payable	4,107	3,558
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Loans receivable	0	0
FHLB stock	0	0
Accrued interest receivable	0	0
Servicing Asset at Amortized Cost, Fair Value	0	0
Deposits	895,139	932,313
Advance payments by borrowers for taxes	0	0
Borrowings	409,621	408,434
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Loans receivable	1,661,155	1,632,248
FHLB stock	0	0
Accrued interest receivable	0	0
Servicing Asset at Amortized Cost, Fair Value	1,533	1,294
Deposits	0	0
Advance payments by borrowers for taxes	0	0
Borrowings	0	0
Accrued interest payable	$ 0	$ 0

Carrying amount of accumulated prepayments received by financial institutions from borrowers for taxes (for example, property taxes) and insurance (for example, property and catastrophe) which will periodically be remitted to the appropriate governmental agency or vendor on behalf of the borrower.

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Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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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 interest payable on debt, including, but not limited to, trade payables.

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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 notes payable.

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Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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The fair value of interest due on receivables that have already been recorded to income.

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No definition available.

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