Quarterly report pursuant to Section 13 or 15(d)

Stock Based Option Compensation and Restricted Stock Compensation (Details Textual)

v3.10.0.1
Stock Based Option Compensation and Restricted Stock Compensation (Details Textual) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Share-based and Restricted Stock Compensation Expense [Abstract]        
Stock-based compensation expense included in operating expense     $ 4,573,000 $ 2,735,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate 0.00%   0.00%  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate 109.00%   109.00%  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate 2.65%   2.44%  
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term 5 years   5 years  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value $ 12.87   $ 11.36  
Share-based Compensation Arrangement by Share-based Payment Award, Option Grants in Period Weighted Average Grant Date Fair Value $ 12.87   $ 11.36  
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Weighted Average Exercise Price $ 16.27   $ 14.38  
Stock Options [Member]        
Share-based and Restricted Stock Compensation Expense [Abstract]        
Stock options granted (in shares) 224,800 185,000 869,800 185,000
Stock-based compensation expense included in operating expense $ 2,673,000 $ 1,243,000 $ 4,573,000 $ 2,735,000
Restricted Stock [Member]        
Share-based and Restricted Stock Compensation Expense [Abstract]        
Stock-based compensation expense included in operating expense $ 172,000 $ 324,000 $ 344,000 $ 686,000