Nature of business and operations (Details) |
12 Months Ended | ||
|---|---|---|---|
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May 18, 2017
USD ($)
$ / shares
shares
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Dec. 31, 2017
USD ($)
segment
$ / shares
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Dec. 31, 2016
USD ($)
$ / shares
|
|
| Class of Stock [Line Items] | |||
| Number of operating segments | segment | 2 | ||
| Common stock, par value (usd per share) | $ / shares | $ 0.001 | $ 0.001 | $ 0.001 |
| Shares issued in acquisition (shares) | shares | 4,662,937 | ||
| Shares issued in acquisition, price per share (in USD per share) | $ / shares | $ 4.02 | ||
| Issuance of stock to acquire American DG Energy, net | $ | $ 18,482,656 | $ 0 | |
| American DG Energy | |||
| Class of Stock [Line Items] | |||
| Outstanding common shares acquired (percent) | 100.00% | ||
| Common stock, par value (usd per share) | $ / shares | $ 0.001 | ||
| Issuance of stock to acquire American DG Energy, net | $ | $ 18,745,007 | ||
| Common stock | |||
| Class of Stock [Line Items] | |||
| Conversion exchange ratio | 0.092 | ||
| Issuance of stock to acquire American DG Energy, net | $ | $ 4,663 | ||
| X | ||||||||||
- Definition Conversion Ratio No definition available.
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- Definition Number of shares of equity interests issued or issuable to acquire entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination. No definition available.
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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 Face amount or stated value per share of common stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. No definition available.
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- Definition Value of stock issued pursuant to acquisitions during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions. No definition available.
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- Details
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- Details
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