Note 4 - Loans - Impaired Loans (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Unpaid Contractual Principal Balance	$ 3,853,793
Recorded Investment With No Allowance	3,163,793
Recorded Investment With Allowance
Total Recorded Investment	3,163,793
Related Allowance
Average Recorded Investment	3,170,587
Interest Recognized	27,313
Commercial Real Estate Portfolio Segment [Member]
Unpaid Contractual Principal Balance	3,800,855	$ 3,867,381
Recorded Investment With No Allowance	3,110,855	3,177,381
Recorded Investment With Allowance
Total Recorded Investment	3,110,855	3,177,381
Related Allowance
Average Recorded Investment	3,144,118	4,180,282
Interest Recognized	26,589	$ 120,193
Residential Portfolio Segment [Member]
Unpaid Contractual Principal Balance	52,938
Recorded Investment With No Allowance	52,938
Recorded Investment With Allowance
Total Recorded Investment	52,938
Related Allowance
Average Recorded Investment	26,469
Interest Recognized	$ 724

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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