Note A - Description of Business and Basis of Presentation (Details Textual) - USD ($)					1 Months Ended		12 Months Ended		23 Months Ended
	Sep. 03, 2019	Feb. 28, 2019	Oct. 10, 2018	Oct. 05, 2018	Feb. 28, 2020	Oct. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Sep. 04, 2018	Oct. 31, 2019	Mar. 31, 2019
Sale of Securities, Value, Available to Issue							$ 150,000,000			$ 80,000,000
Sale of Securities, Value, Remaining Available to Issue							10,900,000
Sale of Securities Covered Under Prospectus Supplement, Value, Anticipated Sales Under Purchase Agreement							4,000,000	$ 5,700,000
Proceeds from Issuance of Common Stock								4,828,000
Revenue from Contract with Customer, Including Assessed Tax							12,839,000	$ 0
License [Member]
Revenue from Contract with Customer, Including Assessed Tax							$ 10,000,000
Cowen and Company, LLC [Member]
Stock Issued During Period, Shares, New Issues									762,338
Proceeds from Issuance of Common Stock									$ 4,900,000
Sale of Stock, Commission Fee									3.00%
RBC Capital Markets, LLC [Member]
Sale of Stock, Authorized Offering Price									$ 50,000,000		$ 3,200,000
Lincoln Park [Member]
Sale of Securities, Value, Available to Issue		$ 15,000,000
Stock Issued During Period, Shares, New Issues							3,401,271
Proceeds from Issuance of Common Stock							$ 5,400,000
Purchase Agreement, Term		3 years
Purchase Agreement, Additional Shares to Be Issued as Commitment Shares		120,200
Lincoln Park [Member] | Subsequent Event [Member]
Sale of Securities, Value, Available to Issue					$ 4,000,000
Purchase Agreement, Term					1 year
Purchase Agreement, Additional Shares to Be Issued as Commitment Shares					308,637
KVK [Member]
License Agreement, Estimated Pre-launch Payments and Costs Reimbursements						$ 3,400,000
License Agreement, Pre-launch Payment Reimbursement Within 10 Days of Initial Adoption Milestone						2,000,000
License Agreement, Maximum Payments Received for Sales Milestones						$ 53,000,000
KVK [Member] | Maximum [Member]
License Agreement, Percentage of Net Sales on Rolling Four Quarter Basis Received						50.00%
KVK [Member] | Minimum [Member]
License Agreement, Percentage of Net Sales on Rolling Four Quarter Basis Received						30.00%
GPC Member | License [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 10,000,000
Revenue Recognition, Milestone Method, Revenue to be Recognized	63,000,000
Revenue Recognition, Milestone Method, Additional Revenue to be Recognized	$ 420,000,000
Royalty Revenue, Percent	10.00%
First ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues							3,401,271	762,338
Proceeds from Issuance of Common Stock							$ 5,400,000
Second ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues							0
Second ATM Agreement [Member] | RBC Capital Markets, LLC [Member] | Maximum [Member]
Sale of Stock, Authorized Offering Price									$ 50,000,000
Underwriting Agreement [Member] | RBC Capital Markets, LLC [Member]
Stock Issued During Period, Shares, New Issues			8,333,334	8,333,334
Shares Issued, Price Per Share			$ 3
Proceeds from Issuance of Common Stock, Net			$ 23,100,000