Note 5 - Loans - Allowance for Loan Losses (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Beginning balance	$ 2,458,911	$ 2,363,086
Provision for loan losses	475,000	410,000
Charge offs	(702,115)	(322,436)
Recoveries	277,538	8,261
Ending balance	2,509,334	2,458,911
Allowance for loan losses, individually		127,213
Allowance for loan losses, collectively	2,509,334	2,331,698
Outstanding loan, individually	3,177,381	5,183,182
Outstanding loan, collectively	340,763,461	330,412,734
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	1,867,397	1,717,749
Provision for loan losses	372,315	419,868
Charge offs	(690,000)	(275,000)
Recoveries	204,660	4,780
Ending balance	1,754,372	1,867,397
Allowance for loan losses, individually		127,213
Allowance for loan losses, collectively	1,754,372	1,740,184
Outstanding loan, individually	3,177,381	5,183,182
Outstanding loan, collectively	235,656,768	228,843,392
Construction and Land Development [Member]
Beginning balance	223,274	204,860
Provision for loan losses	(78,496)	65,850
Charge offs	(12,115)	(47,436)
Recoveries	63,711
Ending balance	196,374	223,274
Allowance for loan losses, individually
Allowance for loan losses, collectively	196,374	223,274
Outstanding loan, individually
Outstanding loan, collectively	18,265,505	18,160,366
Residential Portfolio Segment [Member]
Beginning balance	247,953	247,437
Provision for loan losses	153,673	368
Charge offs
Recoveries		148
Ending balance	401,626	247,953
Allowance for loan losses, individually
Allowance for loan losses, collectively	401,626	247,953
Outstanding loan, individually
Outstanding loan, collectively	63,024,106	59,241,416
Commercial Portfolio Segment [Member]
Beginning balance	87,353	125,260
Provision for loan losses	6,090	(41,240)
Charge offs	0
Recoveries	9,167	3,333
Ending balance	102,610	87,353
Allowance for loan losses, individually
Allowance for loan losses, collectively	102,610	87,353
Outstanding loan, individually
Outstanding loan, collectively	23,323,073	23,613,543
Consumer Portfolio Segment [Member]
Beginning balance	7,027	8,826
Provision for loan losses	3,401	(1,799)
Charge offs
Recoveries
Ending balance	10,428	7,027
Allowance for loan losses, individually
Allowance for loan losses, collectively	10,428	7,027
Outstanding loan, individually
Outstanding loan, collectively	494,009	554,017
Unallocated Financing Receivables [Member]
Beginning balance	25,907	58,954
Provision for loan losses	18,017	(33,047)
Charge offs
Recoveries
Ending balance	43,924	25,907
Allowance for loan losses, individually
Allowance for loan losses, collectively	43,924	25,907
Outstanding loan, individually
Outstanding loan, collectively

A valuation allowance for financing receivables that are expected to be uncollectible.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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