Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation (Details Textual)

v3.7.0.1
Stock Based Compensation (Details Textual) - USD ($)
$ / shares in Units, $ in Millions
6 Months Ended
May 08, 2014
Jun. 30, 2017
Aug. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Common Stock, Capital Shares Reserved for Future Issuance     14,155,292
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum 4.00%    
Share-based Compensation Arrangement by Share-based Payment Award Increase of Shares Offering Date January 1, 2015    
Share-based Compensation Arrangement by Share-based Payment Award, Description   granted at prices not less than 100% of the fair value  
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition   11 months 12 days  
Employee Stock Option [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares   7,393,521  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value   $ 2.90  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value   $ 7.0  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Intrinsic Value   $ 1.69  
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized   $ 5.6