Ameresco, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Goodwill and Intangible Assets- Goodwill (Details)

v2.4.1.9

Goodwill and Intangible Assets- Goodwill (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Balance, December 31, 2014	$ 60,479us-gaap_Goodwill
Goodwill acquired during the year	0us-gaap_GoodwillAcquiredDuringPeriod
Fair value adjustment	(403)
Currency effects	(674)us-gaap_GoodwillTranslationAdjustments
Balance, March 31, 2015	59,402us-gaap_Goodwill
Accumulated Goodwill Impairment	(1,016)	(1,016)
U.S. Regions
Goodwill [Roll Forward]
Balance, December 31, 2014	24,759
Goodwill acquired during the year	0
Fair value adjustment	0
Currency effects	0
Balance, March 31, 2015	24,759
Accumulated Goodwill Impairment	0	0
U.S. Federal
Goodwill [Roll Forward]
Balance, December 31, 2014	3,375
Goodwill acquired during the year	0
Fair value adjustment	0
Currency effects	0
Balance, March 31, 2015	3,375
Accumulated Goodwill Impairment	0	0
Canada
Goodwill [Roll Forward]
Balance, December 31, 2014	3,781
Goodwill acquired during the year	0
Fair value adjustment	0
Currency effects	(318)
Balance, March 31, 2015	3,463
Accumulated Goodwill Impairment	(1,016)	(1,016)
Small-Scale Infrastructure
Goodwill [Roll Forward]
Balance, December 31, 2014	0
Goodwill acquired during the year	0
Fair value adjustment	0
Currency effects	0
Balance, March 31, 2015	0
Accumulated Goodwill Impairment	0	0
Other
Goodwill [Roll Forward]
Balance, December 31, 2014	28,564
Goodwill acquired during the year	0
Fair value adjustment	(403)
Currency effects	(356)
Balance, March 31, 2015	27,805
Accumulated Goodwill Impairment	$ 0	$ 0

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

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+ References

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- Definition

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+ References

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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