Note 5 - Loans - Impaired Loans (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Unpaid Contractual Principal Balance	$ 2,135,045
Recorded Investment With No Allowance	2,135,045
Recorded Investment With Allowance
Total Recorded Investment	2,135,045
Related Allowance
Average Recorded Investment	2,656,213
Interest Recognized	109,750
Commercial Real Estate Portfolio Segment [Member]
Unpaid Contractual Principal Balance	2,084,988	$ 3,867,381
Recorded Investment With No Allowance	2,084,988	3,177,381
Recorded Investment With Allowance
Total Recorded Investment	2,084,988	3,177,381
Related Allowance
Average Recorded Investment	2,631,185	3,177,381
Interest Recognized	106,874	$ 120,193
Residential Portfolio Segment [Member]
Unpaid Contractual Principal Balance	50,057
Recorded Investment With No Allowance	50,057
Recorded Investment With Allowance
Total Recorded Investment	50,057
Related Allowance
Average Recorded Investment	25,029
Interest Recognized	$ 2,876

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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