Annual report pursuant to Section 13 and 15(d)

Stock options and warrants (Schedule of Stock-based Compensation) (Details)

v3.7.0.1
Stock options and warrants (Schedule of Stock-based Compensation) (Details) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]    
Total stock-based compensation $ 545,549 $ 1,143,078
Selling, general and administrative expenses [Member]    
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]    
Total stock-based compensation 542,989 1,016,011
Research and development expenses [Member]    
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]    
Total stock-based compensation $ 2,560 $ 127,067