Note 12 - Income Taxes - Reconciliation of Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Federal tax benefit at statutory rate	(21.00%)	(34.00%)
State tax, net of Federal benefit	(2.90%)	(16.30%)
Change in fair value of warrant		(126.10%)
Change in tax rate		205.50%
Goodwill impairment	7.70%
Orphan drug credit	(1.30%)	(36.00%)
Change in valuation allowance	15.20%	(38.80%)
Stock compensation		1.20%
Other		1.00%
Total provision	(2.30%)	(43.50%)