Note F - Debt Obligations (Details Textual) - USD ($)
12 Months Ended
Feb. 09, 2016
Jun. 02, 2014
Dec. 31, 2016
Jun. 30, 2016
Apr. 30, 2015
Dec. 31, 2013
Series D Redeemable Convertible Preferred Stock [Member]            
Class of Warrant or Right, Number of Securities Called by Warrants or Rights         15,499,324 1,079,453
2021 Notes [Member]            
Debt Instrument, Convertible, Conversion Price $ 17.11          
Debt Instrument, Face Amount $ 86,250,000          
Debt Instrument, Interest Rate, Stated Percentage 5.50%          
Proceeds from Debt, Net of Issuance Costs $ 82,800,000          
Repayments of Long-term Debt $ 18,600,000          
Debt Conversion, Converted Instrument, Shares Issued 58.4454          
Debt Conversion, Original Debt, Amount $ 1,000          
Debt Instrument Repurchase Price Equal to Percentage of Principal Amount 100.00%          
Debt Instrument, Sinking Fund Payment $ 0          
Deerfield Facility Agreement [Member]            
Line of Credit Facility, Maximum Borrowing Capacity   $ 60,000,000        
Line of Credit Facility, Interest Rate at Period End   9.75%        
Debt Covenant, Debt Financing Restriction   $ 750,000        
Deerfield Facility Agreement [Member] | IPO [Member]            
Reclassification of Common Stock Shares   256,410        
Deerfield Facility Agreement [Member] | Deerfield Warrant [Member]            
Class of Warrant or Right, Exercise Price of Warrants or Rights   $ 0.78        
Deerfield Facility Agreement [Member] | Deerfield Warrant [Member] | IPO [Member]            
Class of Warrant or Right, Number of Securities Called by Warrants or Rights   1,923,077        
Deerfield Facility Agreement [Member] | Series D Redeemable Convertible Preferred Stock [Member]            
Class of Warrant or Right, Number of Securities Called by Warrants or Rights   14,423,076        
Own-share Lending Arrangement, Shares, Issued   1,923,077        
Mandatorily Redeemable Preferred Stock, Fair Value Disclosure   $ 1,500,000        
Deerfield Facility Agreement [Member] | Term Notes [Member]            
Proceeds from Secured Notes Payable   15,000,000        
Deerfield Facility Agreement [Member] | Deerfield Convertible Notes [Member]            
Proceeds from Secured Notes Payable   $ 10,000,000        
Debt Instrument, Convertible, Conversion Price   $ 5.85        
Third Line of Credit Agreement [Member] | City National Bank of Florida [Member]            
Line of Credit Facility, Maximum Borrowing Capacity       $ 1,100,000    
Line of Credit Facility, Remaining Borrowing Capacity     $ 400,000      
Long-term Line of Credit     $ 0      
Third Line of Credit Agreement [Member] | City National Bank of Florida [Member] | Prime Rate [Member]            
Debt Instrument, Interest Rate, Stated Percentage     2.77%      
Debt Instrument, Basis Spread on Variable Rate     2.00%