Note R - Subsequent Events (Details Textual) - USD ($)								2 Months Ended			12 Months Ended
	Feb. 08, 2021	Feb. 03, 2021	Jan. 26, 2021	Jan. 12, 2021	Jan. 11, 2021	Jan. 08, 2021	Jan. 01, 2021	Mar. 11, 2021	Mar. 11, 2021	Mar. 11, 2021	Dec. 31, 2020	Sep. 03, 2019	Jun. 02, 2014
Debt Conversion, Converted Instrument, Shares Issued (in shares)											1,777,437
Series B-2 Convertible Preferred Stock [Member]
Convertible Preferred Stock, Conversion Price (in dollars per share)											$ 15.1904	$ 0.9494
Deerfield Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)											$ 93.60
Common Stock [Member] | Deerfield Warrant [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)											120,192		1,923,077
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)											$ 93.60		$ 5.85
Subsequent Event [Member] | The December 2020 Exchange Agreement [Member]
Repayments of Debt							$ 30,300,000
Convertible Notes Payable, Current					$ 7,600,000
Subsequent Event [Member] | The December 2020 Exchange Agreement [Member] | Conversion of Series B-2 Preferred Stock into Common Stock [Member]
Conversion of Stock, Shares Issued (in shares)										4,842,699
Subsequent Event [Member] | The Facility Agreement [Member]
Repayments of Debt	$ 8,000,000
Subsequent Event [Member] | Conversion of the Exchange Note to Series B-2 Preferred Stock and Exchange Warrants [Member] | The December 2020 Exchange Agreement [Member]
Debt Conversion, Original Debt, Amount					31,500,000
Repayments of Debt					$ 30,300,000
Subsequent Event [Member] | Deerfield Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 46.25
Subsequent Event [Member] | Common Stock [Member] | Deerfield Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 46.25
Underwriting Agreement [Member] | Subsequent Event [Member] | Underwriter Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)		18,702		806,932
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 8.125
Class of Warrant or Right Exercised (in shares)								0
Common Stock Issued, Percentage, Over-Allotment Exercise				5.00%
Underwriting Agreement [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member]
Shares and Warrants Issued, Price Per Share (in dollars per share)						$ 6.50
Proceeds from Issuance or Sale of Equity, Total				$ 52,400,000
Underwriting Agreement [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member] | Pre-funded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						926,844
Underwriting Agreement [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member] | Public Offering Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						7,692,307
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 6.50
Class of Warrant or Right, Offering Price, Per Related Warrant (in dollars per share)						$ 0.0001
Underwriting Agreement [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member] | Common Stock [Member]
Stock Issued During Period, Shares, New Issues (in shares)						6,765,463
Shares Issued, Price Per Share (in dollars per share)						$ 6.4999
Underwriting Agreement [Member] | Subsequent Event [Member] | Specified Investors in the Public Offering [Member] | Pre-funded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				926,844
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 0.0001
Maximum Percent of Common Stock Ownership Allowed Per Holder Upon Warrant Exercise				4.99%
Maximum Percent of Common Stock Ownership Allowed Per Holder After Warrant Exercise Upon Holders Selection				9.99%
Stock Issued During Period, Shares, Warrant Exercises (in shares)								926,841
Proceeds from Warrant Exercises								$ 72,000
Over-Allotment Option [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member]
Purchase Agreement Optional Period to Shares (Day)						45 days
Purchase Agreement, Maximum, Additional Shares Available for Purchase During the Optional Period (in shares)						1,153,846
Over-Allotment Option [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member] | Underwriter Warrants [Member]
Over Allotment Options, Number of Shares for Warrants (in shares)						1,153,846
Over-Allotment Option [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member] | Common Stock [Member] | Underwriter Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						754,035
Over-Allotment Option [Member] | Subsequent Event [Member] | Roth Capital Partners, LLC [Member] | Common Stock [Member] | Warrants [Member]
Stock Issued During Period, Shares, New Issues (in shares)		374,035
Underwriting Agreement and the December 2020 Exchange Agreement [Member] | Subsequent Event [Member] | Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				12,078,361
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 6.50
Warrants and Rights Outstanding, Term (Year)				5 years
The December 2020 Exchange Agreement [Member] | Subsequent Event [Member] | Series B-2 Preferred Stock [Member]
Debt Conversion, Converted Instrument, Shares Issued (in shares)				31,476.98412
The December 2020 Exchange Agreement [Member] | Subsequent Event [Member] | Series B-2 Convertible Preferred Stock [Member]
Preferred Stock Convertible Shares Issuable (in shares)				4,842,690
Convertible Preferred Stock, Conversion Price (in dollars per share)				$ 6.4999
The December 2020 Exchange Agreement [Member] | Subsequent Event [Member] | Warrants [Member]
Maximum Percent of Common Stock Ownership Allowed Per Holder Upon Warrant Exercise				4.985%
Stock Issued During Period, Shares, Warrant Exercises (in shares)								2,626,418
Proceeds from Warrant Exercises								$ 14,300,000
Class of Warrant or Right Exercised (in shares)								3,057,395
The December 2020 Exchange Agreement [Member] | Subsequent Event [Member] | Exchange Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				3,632,019
The Inducement Letters [Member] | Subsequent Event [Member] | Existing Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			6,620,358
The Inducement Warrants [Member] | Subsequent Event [Member] | Existing Warrants [Member]
Proceeds from Warrant Exercises			$ 44,000,000
Placement Agent Fee, Percentage			6.00%
The Inducement Warrants [Member] | Subsequent Event [Member] | Inducement Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			7,944,430
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 6.36
Maximum Percent of Common Stock Ownership Allowed Per Holder Upon Warrant Exercise			4.99%
Maximum Percent of Common Stock Ownership Allowed Per Holder After Warrant Exercise Upon Holders Selection			9.99%
Stock Issued During Period, Shares, Warrant Exercises (in shares)									1,676,921
Proceeds from Warrant Exercises									$ 10,700,000
Class of Warrant or Right Exercised (in shares)									1,676,921
Warrants Issued Upon Exchange, Percentage of Shares Issued Upon Exercise			120.00%
Class of Warrant, Purchase Price Per Warrant (in dollars per share)			$ 0.125