Annual report pursuant to Section 13 and 15(d)

Stock options and warrants (Schedule of Fair Value Assumptions) (Details)

v2.4.0.8
Stock options and warrants (Schedule of Fair Value Assumptions) (Details)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Stock Options [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Dividend yield 0.00% 0.00% 0.00%
Expected term 5 years 5 years 5 years
Stock Options [Member] | Minimum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected price volatility 127.00% 121.00% 119.00%
Risk free interest rate 0.65% 0.60% 1.32%
Stock Options [Member] | Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected price volatility 128.00% 127.00% 120.00%
Risk free interest rate 0.76% 1.03% 2.14%
Other Options and Warrants [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Dividend yield   0.00% 0.00%
Expected price volatility   121.00%  
Risk free interest rate   0.74%  
Expected term   5 years  
Other Options and Warrants [Member] | Minimum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected price volatility     119.00%
Risk free interest rate     1.20%
Expected term     3 years
Other Options and Warrants [Member] | Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected price volatility     145.00%
Risk free interest rate     1.95%
Expected term     10 years