Annual report pursuant to Section 13 and 15(d)

Business Acquisitions and Related Transactions - Purchase Price Allocation (Details)

v2.4.0.6
Business Acquisitions and Related Transactions - Purchase Price Allocation (Details) (USD $)
 12 Months Ended 1 Months Ended 1 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Jul. 31, 2011
FAME
Jul. 31, 2012
FAME
Aug. 31, 2011
AEG
Dec. 31, 2011
Ameresco Southwest
Jul. 31, 2012
AIS
Business Acquisition [Line Items]                
Cash       $ 809,557   $ 314,642 $ 0 $ 0
Accounts receivable       320,997   4,138,015 14,149,703 0
Costs and estimated earnings in excess of billings       0   0 11,269,294 163,340
Inventory       0   0 0 47,193
Prepaid expenses and other current assets       107,715   62,345 33,329 0
Project development costs       0   0 0 130,044
Property and equipment and project assets       43,115   7,301 6,447,299 216,297
Goodwill       1,886,945 1,886,945 8,728,169 16,545,434 1,549,467
Intangible assets       2,099,990   4,904,000 7,019,000 2,557,000
Other assets       100   52,062 0 0
Accounts payable       (5,713)   (1,610,734) (1,992,748) 0
Accrued liabilities       (617,731)   (1,011,032) (3,414,198) (65,627)
Billings in excess of cost and estimated earnings       (158,025)   0 0 (100,573)
Deferred taxes and other liabilities       0   (3,591,532) 0 0
Purchase price       4,486,950   11,993,236 50,057,113 4,497,141
Total, net of cash received 4,012,459 66,232,848 6,303,006 3,677,393   11,678,594 50,057,113 4,497,141
Total fair value of consideration       $ 4,486,950   $ 11,993,236 $ 50,057,113 $ 4,497,141