Quarterly report pursuant to Section 13 or 15(d)

Stock-based compensation - Stock-Based Compensation (Details)

v2.4.0.6
Stock-based compensation - Stock-Based Compensation (Details) (USD $)
3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Recognized stock-based compensation $ 57,638 $ 95,053
Compensation cost related to unvested restricted stock awards and stock option awards not yet recognized $ 195,718  
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition 2 years 6 months 25 days  
Tecogen | Amended Plan | Stock options
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Shares of common stock reserved for future issuance 7,355,000  
Number of shares remaining available for future issuance 540,732  
Ilois | 2009 Plan
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Maximum number of shares allowable for issuance 2,000,000