Note 9 - Fair Value of Financial Instruments - Fair Values and Fair Value Measurement Method of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt securities available for sale	$ 61,060	$ 61,333
Loans held for sale	14,900	6,193
Accrued interest receivable	1,879	1,137
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	56,004	75,082
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt securities available for sale	61,060	61,333
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale	14,900	6,193
Loans Receivable, Fair Value Disclosure	465,642	337,710
Federal Home Loan Bank stock	493	404
Accrued interest receivable	1,879	1,137
Derivative contract assets	189
Deposits	555,247	438,624
Other borrowings		1,254
Derivative contract liabilities	189
Off-Balance Sheet Items
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	56,004	75,082
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt securities available for sale	61,060	61,333
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale	15,137	6,296
Loans Receivable, Fair Value Disclosure	481,058	342,435
Federal Home Loan Bank stock	493	404
Accrued interest receivable	1,879	1,137
Derivative contract assets	189
Deposits	555,988	439,208
Other borrowings		1,254
Derivative contract liabilities	189
Off-Balance Sheet Items

The fair value portion of other miscellaneous borrowings owed by the entity.

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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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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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The fair value of financial liabilities, 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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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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