Ameresco, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Business Segment Information (Details)

Business Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Revenues	$ 115,433us-gaap_SalesRevenueNet	$ 100,731us-gaap_SalesRevenueNet
Interest income	151us-gaap_InterestIncomeOperating	13us-gaap_InterestIncomeOperating
Interest expense	1,277us-gaap_InterestExpense	1,181us-gaap_InterestExpense
Depreciation and amortization of intangible assets	5,227	4,805
Unallocated corporate activity	(6,513)amrc_UnallocatedCorporateExpenseSegment	(8,068)amrc_UnallocatedCorporateExpenseSegment
Income (loss) before Income Taxes and Unallocated Corporate Expenses	(577)	(449)
U.S. Regions
Segment Reporting Information [Line Items]
Revenues	47,101	39,832
Interest income	0	0
Interest expense	0	0
Depreciation and amortization of intangible assets	278	314
Unallocated corporate activity	0	0
Income (loss) before Income Taxes and Unallocated Corporate Expenses	1,469	(455)
U.S. Federal
Segment Reporting Information [Line Items]
Revenues	24,143	12,573
Interest income	0	0
Interest expense	0	0
Depreciation and amortization of intangible assets	306	272
Unallocated corporate activity	0	0
Income (loss) before Income Taxes and Unallocated Corporate Expenses	3,258	739
Canada
Segment Reporting Information [Line Items]
Revenues	10,895	16,299
Interest income	1	1
Interest expense	329	412
Depreciation and amortization of intangible assets	243	406
Unallocated corporate activity	0	0
Income (loss) before Income Taxes and Unallocated Corporate Expenses	(5,008)	(1,359)
Small-Scale Infrastructure
Segment Reporting Information [Line Items]
Revenues	12,862	11,149
Interest income	150	12
Interest expense	948	769
Depreciation and amortization of intangible assets	3,390	2,958
Unallocated corporate activity	0	0
Income (loss) before Income Taxes and Unallocated Corporate Expenses	903	672
All Other
Segment Reporting Information [Line Items]
Revenues	20,432	20,878
Interest income	0	0
Interest expense	0	0
Depreciation and amortization of intangible assets	1,010	855
Unallocated corporate activity	0	0
Income (loss) before Income Taxes and Unallocated Corporate Expenses	$ (1,199)	$ (46)