Note 5 - Loans - Modified in a Troubled Debt Restructuring (Details)	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Number of contracts	0		2
Pre-modification			$ 446,064
Post-modification			$ 445,881
Real Estate Portfolio Segment [Member] \| Commercial [Member]
Number of contracts	1		1
Pre-modification	$ 402,430		$ 91,280
Post-modification	$ 402,430		$ 91,097
Real Estate Portfolio Segment [Member] \| Residential [Member]
Number of contracts			1
Pre-modification			$ 354,784
Post-modification			$ 354,784

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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