Note 7 - Premises and Equipment - Summary of Premises and Equipment (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Cost:
Premises and equipment	$ 10,941,505	$ 10,868,665
Less: Accumulated depreciation	4,271,417	4,024,759
	6,670,088	6,843,906
Land [Member]
Cost:
Premises and equipment	2,190,649	2,190,649
Building [Member]
Cost:
Premises and equipment	7,300,466	7,242,297
Furniture and Fixtures [Member]
Cost:
Premises and equipment	$ 1,450,390	$ 1,435,719