Note 3 - Loans and Allowance for Loan Losses (Details Textual)	3 Months Ended	12 Months Ended
Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Loans Charge-off Period	90 days
Performance Period	180 days
Collateral Dependent Loans, Value of Significant Properties	$ 200,000
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Foreclosure	15,000		$ 33,000
Mortgage Loans in Process of Foreclosure, Amount	331,000		365,000
Impaired Financing Receivable, Interest Income, Cash Basis Method, Total	0	$ 0
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	$ 0		0
Financing Receivable, Modifications, Number of Contracts	0	1
Financing Receivable, Troubled Debt Restructuring		$ 179,000
Troubled Debt Restructuring, Principal Charge-offs	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance, Total	$ 511,000		519,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Allowance for Loan Losses	0		0
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Allowance for Loan Losses, Decreases		$ 2,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Provision for Loan Losses	0
Classified Loans [Member]
Allowance for Loan and Lease Losses, Period Increase (Decrease), Total	329,000		333,000
Overall Qualitative Factor [Member]
Allowance for Loan and Lease Losses, Period Increase (Decrease), Total	$ 3,200,000		$ 3,100,000
Bank Overdrafts [Member]
Loans Charge-off Period	45 days

Represents the collateral dependent loans value of significant properties.

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Represents the period of time for a loan charge off.

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Representing the performance period.

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Represents the amount of principal charge-offs for troubled debt restructuring.

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Amount of increase (decrease) of allowance reserve for credit loss.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Amount of reduction in the reserve for loans impairments as a result of current information and events which result in it being probable that estimated cash flows will be significantly higher than previously expected or because actual cash flows are significantly greater than cash flows previously expected for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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- Definition

Amount of expense related to loan loss not accounted for as debt securities, with evidence of deterioration of credit quality.

+ References

No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from foreclosure.

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