Quarterly report pursuant to Section 13 or 15(d)

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)us-gaap_GoodwillPurchaseAccountingAdjustments  
Currency effects (674)us-gaap_GoodwillTranslationAdjustments  
Balance, March 31, 2015 59,402us-gaap_Goodwill  
Accumulated Goodwill Impairment (1,016)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss (1,016)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
U.S. Regions    
Goodwill [Roll Forward]    
Balance, December 31, 2014 24,759us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_OtherUSRegionsMember
 
Goodwill acquired during the year 0us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_OtherUSRegionsMember
 
Fair value adjustment 0us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_OtherUSRegionsMember
 
Currency effects 0us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_OtherUSRegionsMember
 
Balance, March 31, 2015 24,759us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_OtherUSRegionsMember
 
Accumulated Goodwill Impairment 0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_OtherUSRegionsMember
0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_OtherUSRegionsMember
U.S. Federal    
Goodwill [Roll Forward]    
Balance, December 31, 2014 3,375us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_USFederalMember
 
Goodwill acquired during the year 0us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_USFederalMember
 
Fair value adjustment 0us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_USFederalMember
 
Currency effects 0us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_USFederalMember
 
Balance, March 31, 2015 3,375us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_USFederalMember
 
Accumulated Goodwill Impairment 0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_USFederalMember
0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_USFederalMember
Canada    
Goodwill [Roll Forward]    
Balance, December 31, 2014 3,781us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_CanadaMember
 
Goodwill acquired during the year 0us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_CanadaMember
 
Fair value adjustment 0us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_CanadaMember
 
Currency effects (318)us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_CanadaMember
 
Balance, March 31, 2015 3,463us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_CanadaMember
 
Accumulated Goodwill Impairment (1,016)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_CanadaMember
(1,016)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_CanadaMember
Small-Scale Infrastructure    
Goodwill [Roll Forward]    
Balance, December 31, 2014 0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_SmallScaleInfrastructureMember
 
Goodwill acquired during the year 0us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_SmallScaleInfrastructureMember
 
Fair value adjustment 0us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_SmallScaleInfrastructureMember
 
Currency effects 0us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_SmallScaleInfrastructureMember
 
Balance, March 31, 2015 0us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_SmallScaleInfrastructureMember
 
Accumulated Goodwill Impairment 0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_SmallScaleInfrastructureMember
0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= amrc_SmallScaleInfrastructureMember
Other    
Goodwill [Roll Forward]    
Balance, December 31, 2014 28,564us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
 
Goodwill acquired during the year 0us-gaap_GoodwillAcquiredDuringPeriod
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
 
Fair value adjustment (403)us-gaap_GoodwillPurchaseAccountingAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
 
Currency effects (356)us-gaap_GoodwillTranslationAdjustments
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
 
Balance, March 31, 2015 27,805us-gaap_Goodwill
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
 
Accumulated Goodwill Impairment $ 0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember
$ 0us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_CorporateAndOtherMember