Note 5 - Leases - Balance Sheet Information (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Operating Lease, Right-of-Use Asset	$ 1,930,932
Operating lease liabilities - current	459,528	0
Operating lease liabilities – long-term	1,504,328	0
Operating Lease, Liability, Total	1,963,856
Property and equipment, at cost	1,156,162		1,361,920
Accumulated depreciation	(1,149,571)		(1,348,054)
Accumulated depreciation	1,149,571		1,348,054
Property and equipment, net	6,591		13,866
Finance lease liabilities - current	6,651	$ 13,789	13,789
Finance lease liabilities – long-term
Total finance lease liabilities	$ 6,651		$ 13,789
Operating leases (Year)	4 years 219 days
Finance lease (Year)	109 days		1 year 36 days
Operating leases	7.10%
Finance leases	9.00%		7.30%