Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

v2.4.0.6
Document and Entity Information
3 Months Ended
Mar. 31, 2013
May 03, 2013
Class A Common Stock
May 03, 2013
Class B Common Stock
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, 2013    
Document Fiscal Year Focus 2013    
Document Fiscal Period Focus Q1    
Amendment Flag false    
Entity Common Stock, Shares Outstanding   27,439,654 18,000,000