Note 5 - Fair Value of Financial Instruments - Estimated Fair Value of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Securities available for sale	$ 234,939	$ 148,090
Loans receivable, net	622,264	642,630
Reported Value Measurement [Member]
Cash and cash equivalents	149,436	86,269
Securities available for sale	234,939	148,090
Equity securities	217	149
Loans held for sale	5,754	6,186
Loans receivable, net	622,264	642,630
Federal Home Loan Bank stock	1,092	932
Accrued interest receivable	2,062	3,102
Deposits	915,302	795,204
Accrued interest payable	76	140
Commitments to extend credit	(69)	261
Commitments to sell loans	23	(44)
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	149,436	86,269
Securities available for sale	234,939	148,090
Equity securities	217	149
Loans held for sale	5,754	6,186
Loans receivable, net	632,659	648,275
Federal Home Loan Bank stock	1,092	932
Accrued interest receivable	2,062	3,102
Deposits	915,478	795,927
Accrued interest payable	76	140
Commitments to extend credit	(69)	261
Commitments to sell loans	23	(44)
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	149,436	86,269
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	234,939	148,090
Equity securities	217	149
Loans held for sale	5,754	6,186
Loans receivable, net	632,659	648,275
Federal Home Loan Bank stock	1,092	932
Accrued interest receivable	2,062	3,102
Deposits	915,478	795,927
Accrued interest payable	76	140
Portion at Other than Fair Value Measurement [Member]
Commitments to extend credit	219,855	180,330
Commitments to sell loans	$ 26,184	$ 24,746

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 assets (liabilities) to extend credit, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

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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

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

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- Definition

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

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No definition available.

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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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-SubTopic 10
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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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