Note 9 - Borrowed Funds (Details Textual)	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Long-term Line of Credit, Total	$ 0
Long-term Debt, Total	26,500,000	$ 32,500,000
Loans from Other Federal Home Loan Banks	25,000,000
Deposits with Other Federal Home Loan Banks	130,400,000
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available	252,000,000
Federal Home Loan Bank Advances, Maturing 2019 to 2023 [Member]
Federal Home Loan Bank, Advances, Par Value, Total	$ 25,000,000	$ 30,000,000
Federal Home Loan Bank Advances, Number of Advances Outstanding	5	6
Federal Home Loan Bank Advances, Maturing 2019 to 2023 [Member] \| Minimum [Member]
Federal Home Loan Bank, Advances, Interest Rate	1.97%
Federal Home Loan Bank Advances, Maturing 2019 to 2023 [Member] \| Maximum [Member]
Federal Home Loan Bank, Advances, Interest Rate	2.85%
Federal Home Loan Bank Advances, Maturing 2019 to 2023, Advance 1 [Member]
Federal Home Loan Bank, Advances, Par Value, Total	$ 5,000,000	$ 5,000,000
Federal Home Loan Bank Advances, Maturing 2019 to 2023, Advance 2 [Member]
Federal Home Loan Bank, Advances, Par Value, Total	5,000,000	5,000,000
Federal Home Loan Bank Advances, Maturing 2019 to 2023, Advance 3 [Member]
Federal Home Loan Bank, Advances, Par Value, Total	5,000,000	5,000,000
Federal Home Loan Bank Advances, Maturing 2019 to 2023, Advance 4 [Member]
Federal Home Loan Bank, Advances, Par Value, Total	5,000,000	5,000,000
Federal Home Loan Bank Advances, Maturing 2019 to 2023, Advance 5 [Member]
Federal Home Loan Bank, Advances, Par Value, Total	$ 5,000,000	5,000,000
Federal Home Loan Bank Advances, Maturing 2019 to 2023, Advance 6 [Member]
Federal Home Loan Bank, Advances, Par Value, Total		5,000,000
Unsecured Term Loan [Member]
Debt Instrument, Interest Rate, Stated Percentage	4.75%
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 407,400,000
Debt Instrument, Term	5 years
Debt Instrument, Periodic Payment, Principal	$ 250,000
Long-term Debt, Total	1,500,000	2,500,000
Line of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity	7,000,000	7,000,000
Long-term Line of Credit, Total		$ 2,100,000
Debt Instrument, Interest Rate, Stated Percentage		5.75%
Line of Credit Facility, Remaining Borrowing Capacity		$ 4,900,000
Maturity Overnight [Member]
Federal Home Loan Bank, Advances, Par Value, Total	$ 2,100,000	$ 10,800,000
Federal Home Loan Bank, Advances, Interest Rate	5.00%	2.62%

The number of outstanding federal home loan bank advances.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of the required periodic payments applied to principal.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of interest-bearing funds deposited into another Federal Home Loan Banks (FHLBanks).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

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Par amount of advances made and reported by Federal Home Loan Bank (FHLBank).

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount of Federal Home Loan Bank (FHLBank) loans from another FHLBank.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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