Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Description of business and basis of presentation (Policies)
Notes Tables
Notes Details

Revenue - Disaggregation of Revenue (Details)

v3.19.1

Revenue - Disaggregation of Revenue (Details) - USD ($)	3 Months Ended
Revenue - Disaggregation of Revenue (Details) - USD ($)	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Products	$ 3,024,526	$ 3,673,506
Installation services	1,555,864	2,405,655
Maintenance services	2,355,432	2,313,731
Energy production	1,240,809	1,782,535
Total revenues	8,176,631	10,175,427
Products and Services
Disaggregation of Revenue [Line Items]
Products	3,024,526	3,673,506
Installation services	1,555,864	2,405,655
Maintenance services	2,355,432	2,313,731
Energy production	0
Total revenues	6,935,822	8,392,892
Energy Production
Disaggregation of Revenue [Line Items]
Products	0	0
Installation services	0	0
Maintenance services	0	0
Energy production	1,240,809	1,782,535
Total revenues	$ 1,240,809	$ 1,782,535

- Definition

Installation Services Revenue

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Revenue derived from maintenance services provided under contracts or arrangements with clients. For example, it may include the maintenance of software, plant and equipment, and facilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Revenue derived from energy-related services such as supplying various forms of energy from the operation of on-site facilities or cogeneration plants and procurement services provided to energy purchasers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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