Note 6 - Premises and Equipment, Net - Components of Premises and Equipment (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Total cost	$ 17,182,416	$ 17,076,233
Accumulated depreciation and amortization	(7,566,790)	(6,955,329)
Net book value	9,615,626	10,120,904
Land and Land Improvements [Member]
Total cost	2,452,807	2,452,807
Building and Building Improvements [Member]
Total cost	12,276,205	12,218,857
Furniture and Fixtures [Member]
Total cost	2,362,017	2,266,934
Automobiles [Member]
Total cost	$ 91,387	$ 137,635