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Description of business and summary of significant accounting policies - Revenue by Product Line and Services (Details) (USD $)
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3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2013
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Jun. 30, 2012
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Jun. 30, 2013
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Jun. 30, 2012
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| Revenue by Producks and Services [Line Items] | ||||
| Products | $ 807,854 | $ 1,347,719 | $ 2,860,519 | $ 2,837,426 |
| Services | 1,995,606 | 2,037,181 | 3,989,259 | 3,800,002 |
| Total revenues | 2,803,460 | 3,384,900 | 6,849,778 | 6,637,428 |
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Cogeneration
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| Revenue by Producks and Services [Line Items] | ||||
| Products | 457,486 | 637,420 | 1,735,642 | 1,219,670 |
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Chiller
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| Revenue by Producks and Services [Line Items] | ||||
| Products | $ 350,368 | $ 710,299 | $ 1,124,877 | $ 1,617,756 |
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- Details
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- 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
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- 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
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- 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
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