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Stock-based compensation (Tables)
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9 Months Ended |
12 Months Ended |
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Sep. 30, 2013
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Dec. 31, 2012
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Tecogen
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Schedule of Stock Option Activity |
Stock option activity for the nine months ended September 30, 2013 was as follows: | Common Stock Options | Number of
Options | | Exercise
Price
Per
Share | | Weighted
Average
Exercise
Price | | Weighted
Average
Remaining
Life | | Aggregate
Intrinsic
Value | | | Outstanding, December 31, 2012 | | 1,096,500 | | | $0.12-$3.20 | | $ | 1.96 | | | 4.66 years | | $ | 1,356,400 | | | Granted | | 37,500 | | | 3.20 | | | 3.20 | | | — | | | — | | | Exercised | | — | | | — | | | — | | | — | | | — | | | Canceled and forfeited | | — | | | — | | | — | | | — | | | — | | | Expired | | — | | | — | | | — | | | — | | | — | | | Outstanding, September 30, 2013 | | 1,134,000 | | | $0.12-$3.20 | | $ | 2.00 | | | 3.94 years | | $ | 1,356,400 | | | Exercisable, September 30, 2013 | | 815,438 | | | | | $ | 1.73 | | | | | $ | 1,201,075 | | | Vested and expected to vest, September 30, 2013 | | 1,134,000 | | | | | $ | 2.00 | | | | | $ | 1,356,400 | |
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Stock option activity for the year ended December 31, 2012, 2011, and 2010, was as follows: | Common Stock Options | | Number of
Options | | Exercise
Price
Per Share | | Weighted Average
Exercise
Price | | Weighted Average
Remaining
Life | | Aggregate
Intrinsic
Value | | | Outstanding, December 31, 2009 | | | 595,000 | | $ | 0.12 - $2.00 | | $ | 1.28 | | 4.27 years | | $ | 793,500 | | | Granted | | | 25,000 | | $ | 2.60 | | $ | 2.60 | | | | | | | | Exercised | | | | | | | | | | | | | | | | | Canceled and forfeited | | | | | | | | | | | | | | | | | Repurchased | | | | | | | | | | | | | | | | | Expired | | | | | | | | | | | | | | | | | Outstanding, December 31, 2010 | | | 620,000 | | $ | 0.12 - $2.60 | | $ | 1.20 | | 3.30 years | | $ | 793,500 | | | Exercisable, December 31, 2010 | | | 307,500 | | | | | $ | 1.12 | | | | $ | 451,000 | | | Vested and expected to vest, December 31, 2010 | | | 620,000 | | | | | $ | 1.20 | | | | $ | 793,500 | | | Outstanding, December 31, 2010 | | | 620,000 | | $ | 0.12 - $2.60 | | $ | 1.28 | | 3.30 years | | $ | 793,500 | | | Granted | | | 511,500 | | $ | 2.60 - $2.80 | | $ | 2.60 | | | | | | | | Exercised | | | — | | | — | | | — | | | | | | | | Canceled and forfeited | | | — | | | — | | | — | | | | | | | | Repurchased | | | (12,500) | | $ | 1.00 | | $ | 1.00 | | | | | | | | Expired | | | (23,750) | | $ | 1.20 - $2.60 | | $ | 1.48 | | | | | | | | Outstanding, December 31, 2011 | | | 1,095,250 | | $ | 0.12 - $2.80 | | $ | 1.92 | | 5.53 years | | $ | 1,387,150 | | | Exercisable, December 31, 2011 | | | 418,438 | | | | | $ | 1.24 | | | | $ | 815,125 | | | Vested and expected to vest, December 31, 2011 | | | 1,025,250 | | | | | $ | 1.92 | | | | $ | 1,387,150 | | | Outstanding, December 31, 2011 | | | 1,095,250 | | $ | 0.12 - $2.80 | | $ | 1.92 | | 5.53 years | | $ | 1,387,150 | | | Granted | | | 17,500 | | $ | 3.20 | | $ | 3.20 | | | | | | | | Exercised | | | — | | | — | | | — | | | | | | | | Canceled and forfeited | | | (15,938) | | $ | 1.20 - $2.60 | | $ | 1.28 | | | | | | | | Expired | | | (313) | | $ | 2.60 | | $ | 2.60 | | | | | | | | Outstanding, December 31, 2012 | | | 1,096,500 | | $ | 0.12 - $3.20 | | $ | 1.96 | | 4.66 years | | $ | 1,356,400 | | | Exercisable, December 31, 2012 | | | 662,563 | | | | | $ | 1.56 | | | | $ | 1,096,225 | | | Vested and expected to vest, December 31, 2012 | | | 1,096,500 | | | | | $ | 1.96 | | | | $ | 1,356,400 |
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| Summary of Weighted Average Assumptions Used in Black-Scholes Option Pricing |
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The weighted average assumptions used in the Black-Scholes option pricing model for options granted in 2012, 2011, and 2010 are as follows: | | | 2012 | | 2011 | | 2010 | | Stock option awards: | | | | | | | | Expected life | | 6.25 years | | 6.25 years | | 5 years | | Risk-free interest rate | | 0.70% | | 2.46% | | 2.46% | | Expected volatility | | 35.9% - 36.0% | | 33.8% - 35.5% | | 33.3% |
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| Schedule of Restricted Stock Activity |
Restricted stock activity for the nine months ended September 30, 2013 as follows: | | | Number of
Restricted
Stock | | Weighted
Average
Grant Date
Fair Value | | | Unvested, December 31, 2012 | | | 399,070 | | $ | 1.44 | | | Granted | | | — | | | — | | | Vested | | | — | | | — | | | Forfeited | | | (37,500) | | | 2.60 | | | Unvested, September 30, 2013 | | | 361,570 | | $ | 1.31 | |
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Restricted stock activity for the years ended December 31, 2012 and 2011 was as follows: | | | Number of
Restricted
Stock | | Weighted
Average
Grant Date
Fair Value | | | Unvested, December 31, 2009 | | | 414,106 | | $ | 1.24 | | | Granted | | | 19,211 | | | 2.60 | | | Vested | | | — | | | — | | | Forfeited | | | — | | | — | | | Unvested, December 31, 2010 | | | 433,317 | | $ | 1.28 | | | Unvested, December 31, 2010 | | | 433,317 | | $ | 1.28 | | | Granted | | | 50,000 | | | 2.60 | | | Vested | | | — | | | — | | | Forfeited | | | — | | | — | | | Unvested, December 31, 2011 | | | 483,317 | | $ | 1.44 | | | Unvested, December 31, 2011 | | | 483,317 | | $ | 1.44 | | | Granted | | | — | | | — | | | Vested | | | — | | | — | | | Forfeited | | | (84,247 | | | 1.36 | | | Unvested, December 31, 2012 | | | 399,070 | | $ | 1.44 | |
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Ilois
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Schedule of Stock Option Activity |
Stock option activity relating to Ilios for the nine months ended September 30, 2013 was as follows: | Common Stock Options | | Number of
Options | | Exercise
Price
Per
Share | | Weighted
Average
Exercise
Price | | Weighted
Average
Remaining
Life | | Aggregate
Intrinsic
Value | | | Outstanding, December 31, 2012 | | | 575,000 | | | $0.10-$0.50 | | $ | 0.29 | | | 7.44 years | | $ | 120,000 | | | Granted | | | — | | | — | | | — | | | | | | | | | Exercised | | | — | | | — | | | — | | | | | | | | | Canceled and forfeited | | | — | | | — | | | — | | | | | | | | | Expired | | | — | | | — | | | — | | | | | | | | | Outstanding, September 30, 2013 | | | 575,000 | | | $0.10-$0.50 | | $ | 0.29 | | | 6.69 years | | $ | 120,000 | | | Exercisable, September 30, 2013 | | | 62,500 | | | | | $ | 0.50 | | | | | $ | — | | | Vested and expected to vest, September 30, 2013 | | | 575,000 | | | | | $ | 0.29 | | | | | $ | 120,000 | |
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Stock option activity for the year ended December 31, 2012, 2011, and 2010, was as follows: | Common Stock Options | | Number of
Options | | Exercise
Price
Per Share | | Weighted Average
Exercise
Price | | Weighted Average
Remaining
Life | | Aggregate
Intrinsic
Value | | | Outstanding, December 31, 2009 | | | 595,000 | | $ | 0.12 - $2.00 | | $ | 1.28 | | 4.27 years | | $ | 793,500 | | | Granted | | | 25,000 | | $ | 2.60 | | $ | 2.60 | | | | | | | | Exercised | | | | | | | | | | | | | | | | | Canceled and forfeited | | | | | | | | | | | | | | | | | Repurchased | | | | | | | | | | | | | | | | | Expired | | | | | | | | | | | | | | | | | Outstanding, December 31, 2010 | | | 620,000 | | $ | 0.12 - $2.60 | | $ | 1.20 | | 3.30 years | | $ | 793,500 | | | Exercisable, December 31, 2010 | | | 307,500 | | | | | $ | 1.12 | | | | $ | 451,000 | | | Vested and expected to vest, December 31, 2010 | | | 620,000 | | | | | $ | 1.20 | | | | $ | 793,500 | | | Outstanding, December 31, 2010 | | | 620,000 | | $ | 0.12 - $2.60 | | $ | 1.28 | | 3.30 years | | $ | 793,500 | | | Granted | | | 511,500 | | $ | 2.60 - $2.80 | | $ | 2.60 | | | | | | | | Exercised | | | — | | | — | | | — | | | | | | | | Canceled and forfeited | | | — | | | — | | | — | | | | | | | | Repurchased | | | (12,500) | | $ | 1.00 | | $ | 1.00 | | | | | | | | Expired | | | (23,750) | | $ | 1.20 - $2.60 | | $ | 1.48 | | | | | | | | Outstanding, December 31, 2011 | | | 1,095,250 | | $ | 0.12 - $2.80 | | $ | 1.92 | | 5.53 years | | $ | 1,387,150 | | | Exercisable, December 31, 2011 | | | 418,438 | | | | | $ | 1.24 | | | | $ | 815,125 | | | Vested and expected to vest, December 31, 2011 | | | 1,025,250 | | | | | $ | 1.92 | | | | $ | 1,387,150 | | | Outstanding, December 31, 2011 | | | 1,095,250 | | $ | 0.12 - $2.80 | | $ | 1.92 | | 5.53 years | | $ | 1,387,150 | | | Granted | | | 17,500 | | $ | 3.20 | | $ | 3.20 | | | | | | | | Exercised | | | — | | | — | | | — | | | | | | | | Canceled and forfeited | | | (15,938) | | $ | 1.20 - $2.60 | | $ | 1.28 | | | | | | | | Expired | | | (313) | | $ | 2.60 | | $ | 2.60 | | | | | | | | Outstanding, December 31, 2012 | | | 1,096,500 | | $ | 0.12 - $3.20 | | $ | 1.96 | | 4.66 years | | $ | 1,356,400 | | | Exercisable, December 31, 2012 | | | 662,563 | | | | | $ | 1.56 | | | | $ | 1,096,225 | | | Vested and expected to vest, December 31, 2012 | | | 1,096,500 | | | | | $ | 1.96 | | | | $ | 1,356,400 | |
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| Summary of Weighted Average Assumptions Used in Black-Scholes Option Pricing |
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For the Ilios awards, the weighted average assumptions used in the Black-Scholes option pricing model for options granted in 2012 and 2011 are as follows: | | | 2012 | | 2011 | | | Stock option awards: | | | | | | | Expected life | | 6.25 years | | 6.25 years | | | Risk-free interest rate | | 2.03% | | 2.03% | | | Expected volatility | | 36.1% | | 34.2% | |
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| Schedule of Restricted Stock Activity |
Restricted stock activity for the Ilios awards, for the nine months ended September 30, 2013 was as follows: | | | Number of
Restricted
Stock | | Weighted
Average
Grant Date
Fair Value | | | Unvested, December 31, 2012 | | | 510,000 | | $ | 0.26 | | | Granted | | | — | | | — | | | Vested | | | — | | | — | | | Forfeited | | | (200,000) | | | 0.50 | | | Unvested, September 30, 2013 | | | 310,000 | | $ | 0.10 | |
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Restricted stock activity for the Ilios awards, for the years ended December 31, 2012, 2011, and 2010 was as follows: | | | Number of
Restricted
Stock | | Weighted Average
Grant Date Fair
Value | | | Unvested, December 31, 2009 | | | 360,000 | | $ | 0.10 | | | Granted | | | — | | | — | | | Vested | | | — | | | — | | | Forfeited | | | — | | | — | | | Unvested, December 31, 2010 | | | 360,000 | | $ | 0.10 | | | Unvested, December 31, 2010 | | | 360,000 | | $ | 0.10 | | | Granted | | | 200,000 | | | 0.50 | | | Vested | | | — | | | — | | | Forfeited | | | — | | | — | | | Unvested, December 31, 2011 | | | 560,000 | | $ | 0.24 | | | Unvested, December 31, 2011 | | | 560,000 | | $ | 0.24 | | | Granted | | | — | | | — | | | Vested | | | — | | | — | | | Forfeited | | | (50,000) | | | 0.10 | | | Unvested, December 31, 2012 | | | 510,000 | | $ | 0.26 | |
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