General form of registration statement for all companies including face-amount certificate companies

Noncontrolling interests - Narrative (Details)

v2.4.0.8
Noncontrolling interests - Narrative (Details) (USD $)
Share data in Millions, except Per Share data, unless otherwise specified
9 Months Ended 12 Months Ended 12 Months Ended 12 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Sep. 30, 2013
Ilios
Dec. 31, 2012
Ilios
Dec. 31, 2011
Ilios
Dec. 31, 2010
Ilios
Dec. 31, 2012
Ilios
Private placement to accredited investors
Jul. 24, 2009
Ilios
Private placement to accredited investors
Dec. 31, 2012
Ilios
Private placement to Tecogen
Dec. 31, 2011
Ilios
Private placement to Tecogen
Dec. 28, 2012
Ilios
Private placement to Tecogen
Dec. 29, 2011
Ilios
Private placement to Tecogen
Jun. 03, 2011
Ilios
Private placement to Tecogen
Noncontrolling Interest [Line Items]                                
The Companys ownership percentage in subsidiary     65.00%     65.00% 65.00% 67.40% 63.00%              
Subsidiary cumulative number of shares sold                   1.0   1.0 1.5      
Subsidiary sale of stock, price in usd per share                   $ 0.50 $ 0.50 $ 0.50 $ 0.50 $ 0.50 $ 0.50 $ 0.50
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Change Due to Net Income Attributable to Parent and Effects of Changes, Net [Abstract]                                
Net loss attributable to Tecogen Inc. $ (3,338,552) $ (1,509,891) $ (1,636,957) $ (1,574,501) $ (355,308)                      
Transfers (to) from the noncontrolling interest                                
Decrease in Tecogen’s paid-in capital for purchase of 1,000,000 and 1,500,000 Ilios common shares in 2012 and 2011, respectively     (174,958) (261,174)                        
Increase in Tecogen’s paid-in capital upon the sale of 1,000,000 Ilios common shares 0 289,605 289,606                          
Net transfers to noncontrolling interest 0 289,605 114,648 (261,174) 0                      
Change from net loss attributable to Tecogen Inc. and transfers to noncontrolling interest (3,338,552) (1,220,286) (1,522,309) (1,835,675) (355,308)                      
Subsidiary aggregate proceeds from stock transactions                   $ 500,000   $ 500,000 $ 750,000