Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

v2.4.1.9
Document and Entity Information
3 Months Ended
Mar. 31, 2015
May 04, 2015
Entity Information [Line Items]    
Entity Registrant Name Ameresco, Inc.  
Entity Central Index Key 0001488139  
Current Fiscal Year End Date --12-31  
Entity Filer Category Accelerated Filer  
Document Type 10-Q  
Document Period End Date Mar. 31, 2015  
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q1  
Amendment Flag false  
Common Class A    
Entity Information [Line Items]    
Common Stock   28,494,092dei_EntityCommonStockSharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassAMember
Common Class B    
Entity Information [Line Items]    
Common Stock   18,000,000dei_EntityCommonStockSharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonClassBMember