Note 2 - Summary of Significant Accounting Policies - Customers and Accounts Receivable (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Percentage of revenue	100.00%	100.00%
Variance
Department of Defense [Member]
Percentage of revenue	57.20%	46.30%
Variance	10.90%
Incuron [Member]
Percentage of revenue	42.80%	53.70%
Variance	(10.90%)