Annual report pursuant to Section 13 and 15(d)

Stock Plans (Details Textual)

v3.19.1
Stock Plans (Details Textual) - USD ($)
1 Months Ended 12 Months Ended
May 31, 2009
Oct. 31, 2007
Jul. 31, 2002
Aug. 31, 2001
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Aug. 31, 2018
Feb. 28, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Weighted-average period for recognizing non-vested stock option         2 years 3 months 18 days        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number         665,000 455,000      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number         576,000        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value         $ 3.21 $ 11.58 $ 18.60    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross         245,000        
Employee Stock Option [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized         $ 103,000        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number         600,000 600,000      
2002 Plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized     217,000            
Share Based Compensation Arrangement By Share Based Payment Award Percentage Of Fair Market Value Of Common Stock For Calculating Exercise Price     100.00%            
Options To Purchase Common Stock         86,626        
2001 Non-Qualified Plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized       53,031          
Share Based Compensation Arrangement By Share Based Payment Award Percentage Of Fair Market Value Of Common Stock For Calculating Exercise Price       100.00%          
Options To Purchase Common Stock         28,917        
2015 Plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized               583,334  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number         479,030        
2014 Plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized                 75,758
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number         42,861        
Non Qualified Option plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price $ 26.04 $ 79.20              
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 48 months 48 months              
Award [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross         245,010        
Dr. Rubin [Member] | Non Qualified Option plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 18,637 13,258              
Mr. Bhonsle [Member] | Non Qualified Option plan [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 9,394