Note 8 - Loans and Allowance for Credit Losses (Details Textual)	3 Months Ended
Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Impaired Financing Receivable, Interest Income, Cash Basis Method, Total	$ 0	$ 0
Number of Impaired Loans	19		21
Impaired Financing Receivable, Recorded Investment, Total	$ 1,106,444		$ 1,503,940
Financing Receivable, Modifications, Number of Contracts	0	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Real Estate Acquired Through Foreclosure	$ 196,000
Mortgage Loans in Process of Foreclosure, Amount	92,925		276,815
Residential Portfolio Segment [Member]
Real Estate Acquired Through Foreclosure	196,000		0
Impaired Loan [Member]
Payments for (Proceeds from) Loans Receivable, Total	$ 22,000
Additional Impaired Loans [Member]
Number of Impaired Loans	1
Impaired Financing Receivable, Recorded Investment, Total	$ 18,500
Troubled Debt Restructurings [Member]
Impaired Financing Receivable, Recorded Investment, Total	68,000		$ 70,000
Proceeds from Impaired Loans, Principal Payment	$ 2,000
Written Down and Moved to OREO [Member]
Number of Impaired Loans	1
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 277,000
Impaired Loans Paid Off [Member]
Number of Impaired Loans	2
Impaired Financing Receivable, Recorded Investment, Total	$ 109,000

Represents the number of impaired loans.

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- Definition

The cash inflow associate with the principal payment received from impaired loans.

+ References

No definition available.

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Reflects the amount of the write-down related to a troubled debt restructuring.

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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.

+ References

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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- Definition

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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- Definition

The net amount paid or received by the reporting entity associated with purchase (sale or collection) of loans receivable arising from the financing of goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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