Note 21 - Fair Value of Financial Instruments - Estimated Fair Value of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale	$ 107,592	$ 79,859
Equity securities	167	121
Loans receivable, net	596,392	586,688
Reported Value Measurement [Member]
Cash and cash equivalents	44,399	20,709
Securities available for sale	107,592	79,859
Equity securities	167	121
Loans held for sale	3,606	3,444
Loans receivable, net	596,392	586,688
FHLB stock	854	867
Accrued interest receivable	2,251	2,356
Deposits	673,870	623,352
Accrued interest payable	420	346
Commitments to extend credit	14	40
Commitments to sell loans	(16)	(56)
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	44,399	20,709
Securities available for sale	107,592	79,859
Equity securities	167	121
Loans held for sale	3,606	3,444
Loans receivable, net	600,863	578,978
FHLB stock	854	867
Accrued interest receivable	2,251	2,356
Deposits	673,945	623,439
Accrued interest payable	420	346
Commitments to extend credit	14	40
Commitments to sell loans	(16)	(56)
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	44,399
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	107,592
Equity securities	167
Loans held for sale	3,606
Loans receivable, net	600,863
FHLB stock	854
Accrued interest receivable	2,251
Deposits	673,945
Accrued interest payable	420
Portion at Other than Fair Value Measurement [Member]
Commitments to extend credit	178,804	146,978
Commitments to sell loans	$ 10,098	$ 7,289

Fair value portion of accrued interest payable.

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Fair value portion of accrued interest receivable.

+ 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

No definition available.

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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 326
-SubTopic 30
-Section 45
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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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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