Acquisition of American DG Energy Inc. - Pro Forma Information (Details) - American DG Energy - USD ($)  | 
12 Months Ended | |
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Dec. 31, 2017  | 
Dec. 31, 2016  | 
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| Business Acquisition [Line Items] | ||
| Total revenues | $ 36,232,650 | $ 29,674,375 | 
| Net income (loss) | $ 113,255 | $ (253,132) | 
| Basic earnings (loss) per share (in USD per share) | $ 0.01 | $ (0.01) | 
| Diluted earnings (loss) per share (in USD per share) | $ 0.01 | $ (0.01) | 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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