Note 5 - Fair Value of Financial Instruments - Estimated Fair Value of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities available for sale	$ 284,648	$ 285,765
Loans receivable, net	679,124	652,502
Reported Value Measurement [Member]
Cash and cash equivalents	29,176	94,143
Securities available for sale	284,648	285,765
Equity securities	217	248
Loans held for sale	1,882	5,575
Loans receivable, net	679,124	652,502
Federal Home Loan Bank stock	1,283	1,092
Accrued interest receivable	2,269	2,132
Deposits	920,398	950,666
Accrued interest payable	58	63
Commitments to extend credit	(131)	(26)
Commitments to extend credit	131	26
Commitments to sell loans	43	12
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	29,176	94,143
Securities available for sale	284,648	285,765
Equity securities	217	248
Loans held for sale	1,882	5,575
Loans receivable, net	672,369	661,298
Federal Home Loan Bank stock	1,283	1,092
Accrued interest receivable	2,269	2,132
Deposits	919,450	950,558
Accrued interest payable	58	63
Commitments to extend credit	(131)	(26)
Commitments to extend credit	131	26
Commitments to sell loans	43	12
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	29,176	94,143
Securities available for sale
Equity securities
Loans held for sale
Loans receivable, net
Federal Home Loan Bank stock
Accrued interest receivable
Deposits
Accrued interest payable
Commitments to extend credit
Commitments to extend credit
Commitments to sell loans
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Securities available for sale	284,648	285,765
Equity securities	217	248
Loans held for sale	1,882	5,575
Loans receivable, net	672,369	661,298
Federal Home Loan Bank stock	1,283	1,092
Accrued interest receivable	2,269	2,132
Deposits	919,450	950,558
Accrued interest payable	58	63
Commitments to extend credit
Commitments to extend credit
Commitments to sell loans
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Securities available for sale
Equity securities
Loans held for sale
Loans receivable, net
Federal Home Loan Bank stock
Accrued interest receivable
Deposits
Accrued interest payable
Commitments to extend credit	(195,861)	(195,141)
Commitments to extend credit	195,861	195,141
Commitments to sell loans	$ 13,345	$ 12,340

Fair value portion of accrued interest payable.

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Fair value portion of accrued interest receivable.

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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.

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

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- Definition

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

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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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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