Ameresco, Inc. Annual report pursuant to Section 13 and 15(d)

Business Segment Information - Additional Information (Details)

v3.6.0.2

Business Segment Information - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Unallocated corporate activity	$ 16,367	$ 292	$ 6,292
Unallocated corporate expense segment	(32,181)	$ (25,671)	$ (27,621)
Customer Who Declared Bankruptcy
Segment Reporting Information [Line Items]
Unallocated corporate expense segment	$ 2,870
Various Governments \| Sales Revenue, Net \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk percentage	75.00%	75.00%	75.00%
U.S. Federal Government \| Sales Revenue, Net \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk percentage	27.30%	20.20%	17.90%
Canada \| Operating Segments
Segment Reporting Information [Line Items]
Interest and debt expense	$ 1,934

- Definition

Unallocated Corporate Expense Segment

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
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-Name Accounting Standards Codification
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- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Interest and debt related expenses associated with nonoperating financing activities of the entity.

+ References

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-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
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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.

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