Note 21 - Fair Value of Financial Instruments - Estimated Fair Value of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Securities available for sale	$ 148,090	$ 107,592
Loans receivable, net	642,630	596,392
Reported Value Measurement [Member]
Cash and cash equivalents	86,269	44,399
Securities available for sale	148,090	107,592
Equity securities	149	167
Loans held for sale	6,186	3,606
Loans receivable, net	642,630	596,392
FHLB stock	932	854
Accrued interest receivable	3,102	2,251
Deposits	795,204	673,870
Accrued interest payable	140	420
Commitments to extend credit	261	14
Commitments to sell loans	(44)	(16)
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	86,269	44,399
Securities available for sale	148,090	107,592
Equity securities	149	167
Loans held for sale	6,186	3,606
Loans receivable, net	648,275	600,863
FHLB stock	932	854
Accrued interest receivable	3,102	2,251
Deposits	795,927	673,945
Accrued interest payable	140	420
Commitments to extend credit	261	14
Commitments to sell loans	(44)	(16)
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	86,269
Securities available for sale
Equity securities
Loans held for sale
Loans receivable, net
FHLB stock
Accrued interest receivable
Deposits
Accrued interest payable
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	148,090
Equity securities	149
Loans held for sale	6,186
Loans receivable, net	648,275
FHLB stock	932
Accrued interest receivable	3,102
Deposits	795,927
Accrued interest payable	140
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
FHLB stock
Accrued interest receivable
Deposits
Accrued interest payable
Commitments to extend credit
Commitments to sell loans
Portion at Other than Fair Value Measurement [Member]
Cash and cash equivalents
Securities available for sale
Equity securities
Loans held for sale
Loans receivable, net
FHLB stock
Accrued interest receivable
Deposits
Accrued interest payable
Commitments to extend credit	180,330	178,804
Commitments to sell loans	$ 24,746	$ 10,098

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).

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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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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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