Quarterly report pursuant to Section 13 or 15(d)

Stock options and warrants (Stock incentive plan options) (Narrative) (Details)

v2.4.0.8
Stock options and warrants (Stock incentive plan options) (Narrative) (Details) (USD $)
3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Minimum [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expiration period 3 years  
Maximum [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expiration period 5 years  
Stock Incentive Plan [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options granted 652,100  
Weighted average exercise price of options granted $ 2.28  
Weighted-average fair value of options granted $ 1.91  
Options forfeited 23,605  
Options expired 19,939 6,644
Options forfeited, unvested 3,667  
Options expired, exercise price $ 39.10 $ 2.43
Options forfeited, unvested, exercise price $ 2.04  
Fair value of options vested $ 233,000 $ 532,000
Expected to vest 646,000  
Unrecognized compensation cost $ 919,000  
Unrecognized compensation cost, period for recognition 1 year  
Stock Incentive Plan [Member] | Independent Directors [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options granted 221,000  
Weighted average exercise price of options granted $ 2.27  
Expiration period 10 years  
Vesting period 1 year  
Vesting rate 25.00%  
Stock Incentive Plan [Member] | Officers and Employees [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options granted 406,100  
Weighted average exercise price of options granted $ 2.28  
Expiration period 10 years  
Vesting period 2 years  
Vesting rate 50.00%  
Stock Incentive Plan [Member] | Consultant [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Options granted 25,000  
Weighted average exercise price of options granted $ 2.38  
Expiration period 10 years  
Vesting period 2 years  
Vesting rate 50.00%