Note 7 - Fair Value - Carrying Amount and Fair Value of Financial Instruments Included in the Consolidated Balance Sheet (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Debt securities, fair value	$ 99,652,000	$ 120,107,000
Securities - equities	12,000	19,000
Loans held for sale	314,000
Federal bank stock	5,799,000	5,790,000
Fair Value, Inputs, Level 1 [Member]
Debt securities, fair value
Securities - equities	12,000	19,000
Fair Value, Inputs, Level 2 [Member]
Debt securities, fair value	96,130,000	116,085,000
Securities - equities
Fair Value, Inputs, Level 3 [Member]
Debt securities, fair value	3,522,000	4,022,000
Securities - equities
Reported Value Measurement [Member]
Cash and cash equivalents	21,903,000	14,986,000
Interest earning time deposits	6,412,000	9,698,000
Debt securities, fair value	99,652,000	120,107,000
Securities - equities	12,000	19,000
Loans held for sale	314,000
Loans, net	831,386,000	695,348,000
Federal bank stock	5,799,000	5,790,000
Accrued interest receivable	4,231,000	2,600,000
Total	969,709,000	848,548,000
Deposits	899,516,000	787,124,000
Borrowed funds	32,050,000	28,550,000
Accrued interest payable	534,000	616,000
Total	932,100,000	816,290,000
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	21,903,000	14,986,000
Interest earning time deposits	6,412,000	9,698,000
Debt securities, fair value	99,652,000	120,107,000
Securities - equities	12,000	19,000
Loans held for sale	314,000
Loans, net	829,528,000	697,990,000
Federal bank stock
Accrued interest receivable	4,231,000	2,600,000
Total	962,052,000	845,400,000
Deposits	905,239,000	793,999,000
Borrowed funds	32,298,000	29,133,000
Accrued interest payable	534,000	616,000
Total	938,071,000	823,748,000
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	21,903,000	14,986,000
Interest earning time deposits
Debt securities, fair value
Securities - equities	12,000	19,000
Loans held for sale
Loans, net
Federal bank stock
Accrued interest receivable	81,000	78,000
Total	21,996,000	15,083,000
Deposits	707,194,000	569,357,000
Borrowed funds
Accrued interest payable	36,000	51,000
Total	707,230,000	569,408,000
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Interest earning time deposits	6,412,000	9,698,000
Debt securities, fair value	96,130,000	116,085,000
Securities - equities
Loans held for sale	314,000
Loans, net
Accrued interest receivable	497,000	419,000
Total	103,353,000	126,202,000
Deposits	198,045,000	224,642,000
Borrowed funds	32,298,000	29,133,000
Accrued interest payable	498,000	565,000
Total	230,841,000	254,340,000
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Interest earning time deposits
Debt securities, fair value	3,522,000	4,022,000
Securities - equities
Loans held for sale
Loans, net	829,528,000	697,990,000
Federal bank stock
Accrued interest receivable	3,653,000	2,103,000
Total	836,703,000	704,115,000
Deposits
Borrowed funds
Accrued interest payable
Total

The fair value of deposit assets.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. This item represents the amount of accrued interest payable as of the balance sheet date.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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 debt instrument payable, including, but not limited to, notes payable and loans payable.

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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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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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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, before valuation allowance, of financing receivable classified as held-for-sale.

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Fair value portion of receivables, including, but not limited to, trade account receivables, note receivables, and loan receivables.

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