Note 9 - Leases, Commitments and Contingencies (Details Textual)	12 Months Ended
	Dec. 31, 2019 USD ($) a	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2019 USD ($)	Nov. 30, 2018 USD ($) ft²	Mar. 31, 2012 USD ($)
Operating Lease, Maximum Commitment To Incur Construction Cost				$ 3,100,000
Operating Lease, Construction Cost	$ 2,800,000
Finance Lease, Right-of-Use Asset	$ 1,981,002
Lessee, Finance Lease, Discount Rate	7.50%
Operating Leases, Rent Expense, Net, Total		$ 953,733
Contingent Consideration, Amount						$ 400,000
Contingent Consideration, Amount Paid			$ 20,000
Contingent Consideration, Due Upon First Dosing Of First Patient		80,000
Contingent Consideration, Remainder Due		300,000
Maximum Net Sales Threshold As Basis For Payment Of Future Contingent Royalties		$ 1,500,000
CSC Financing [Member]
Lessee, Finance Lease, Term of Contract	3 years
Percentage of Initial Financed Amount	23.00%
Lease Extension, November 2018 [Member]
Area of Real Estate Property	45,000				8,264
Operating Lease, Letter Of Intent Expansion Of Lease In Exchange For Termination Of Lease, Area Of Property Leased | ft²					4,400
Operating Lease, Letter of Intent Tenant Allowance					$ 1,000,000
Operating Lease, Incremental Rent Over Terminated Lease					$ 100,000