|
Description of business and summary of significant accounting policies - Revenue by Product Line and Services (Details) (USD $)
|
3 Months Ended | |
|---|---|---|
|
Mar. 31, 2014
|
Mar. 31, 2013
|
|
| Revenue by Producks and Services [Line Items] | ||
| Products | $ 1,944,776 | $ 2,052,665 |
| Services | 2,270,981 | 1,993,653 |
| Total revenues | 4,215,757 | 4,046,318 |
|
Cogeneration
|
||
| Revenue by Producks and Services [Line Items] | ||
| Products | 1,154,269 | 1,278,156 |
|
Chiller
|
||
| Revenue by Producks and Services [Line Items] | ||
| Products | 790,507 | 774,509 |
|
Service Contracts [Member]
|
||
| Revenue by Producks and Services [Line Items] | ||
| Services | 1,772,981 | 1,745,946 |
|
Installations [Member]
|
||
| Revenue by Producks and Services [Line Items] | ||
| Services | $ 498,000 | $ 247,707 |
| X | ||||||||||
|
- Details
|
| X | ||||||||||
|
- Definition
Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|