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

Business Acquisitions and Related Transactions - Narrative (Details)

v3.10.0.1

Business Acquisitions and Related Transactions - Narrative (Details)	1 Months Ended	3 Months Ended	6 Months Ended
	Jan. 31, 2017 USD ($) project	Jun. 30, 2018 USD ($)	Jun. 30, 2018 USD ($) project	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Number of projects acquired \| project			4
Energy assets, net		$ 404,888,000	$ 404,888,000	$ 356,443,000
Cash acquired from acquisition		0
Solar Photovoltaic Projects
Business Acquisition [Line Items]
Number of projects acquired \| project	2
Initial cash payment	$ 2,409,000
Debt assumed	$ 5,635,000
Solar Project 1
Business Acquisition [Line Items]
Number of projects acquired \| project			1
Fair value of consideration			$ 20,770,000
Business combination, contingent consideration, liability		1,307,000	1,307,000
Solar Projects 1 and 2
Business Acquisition [Line Items]
Initial cash payment			32,000,000
Fair value of consideration			33,000,000
Energy assets, net		32,000,000	32,000,000
Undisclosed Name of Acquiree One
Business Acquisition [Line Items]
Initial cash payment		1,901,000
Debt assumed		0
Fair value of consideration		0
4 Solar Projects
Business Acquisition [Line Items]
Initial cash payment			3,000,000
Fair value of consideration			0
Energy assets, net		$ 3,000,000	$ 3,000,000
Minimum
Business Acquisition [Line Items]
Estimated useful life			1 year
Minimum \| Solar Photovoltaic Projects
Business Acquisition [Line Items]
Estimated useful life			1 year
Maximum
Business Acquisition [Line Items]
Estimated useful life			15 years
Maximum \| Solar Photovoltaic Projects
Business Acquisition [Line Items]
Estimated useful life			15 years

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