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

Business Acquisitions and Related Transactions - Narrative (Details)

v3.6.0.2

Business Acquisitions and Related Transactions - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Dec. 31, 2016	Aug. 31, 2014	Dec. 31, 2016	Dec. 31, 2014
Business Acquisition [Line Items]
Weighted average useful life				8 years 2 months 12 days
Solar PV project
Business Acquisition [Line Items]
Initial cash payment	$ 3,575
Debt assumed	$ 9,503
EEX
Business Acquisition [Line Items]
Initial cash payment		$ 9,054
Security deposit with third-party escrow agent		$ 834
Minimum
Business Acquisition [Line Items]
Intangible assets amortization period			1 year
Maximum
Business Acquisition [Line Items]
Intangible assets amortization period			15 years

- Definition

Business Acquisition, Cost of Acquired Entity, Security Deposit in Escrow

+ References

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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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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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB
-Name Accounting Standards Codification
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