Ameresco, Inc. Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Cover
- Cover Page
Financial Statements
Notes to Financial Statements
Accounting Policies
- SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
Notes Tables
Notes Details

VARIABLE INTEREST ENTITIES AND EQUITY METHOD INVESTMENTS - Additional Information (Details)

v3.26.3

VARIABLE INTEREST ENTITIES AND EQUITY METHOD INVESTMENTS - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended							6 Months Ended	9 Months Ended		12 Months Ended
	May 12, 2026	Sep. 30, 2026	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	Aug. 25, 2026	May 11, 2026	May 04, 2026
Variable Interest Entity [Line Items]
Payments of financing costs										$ 4,512	$ 7,411
Net income (loss) attributable to noncontrolling interest		$ 14,921	$ 10,126	$ 3,837	$ 6,489	$ 3,245	$ 2,591	$ (186)	$ 2,405	28,884	$ 5,650	$ 12,140
Revolving Credit Facility \| Variable Rate Construction Facility, Due December 2027 \| Line of Credit
Variable Interest Entity [Line Items]
Contributions to joint venture	$ 57,942
Payments of financing costs	5,371
HA Sustainable Infrastructure Capital, Inc.
Variable Interest Entity [Line Items]
JV investor investment in joint venture	400,000												$ 66,000
Contributions to joint venture	233,800
HA Sustainable Infrastructure Capital, Inc.
Variable Interest Entity [Line Items]
JV investor investment in joint venture															$ 400,000
Remaining interest in joint venture	$ 166,200
Neogenyx Fuels LLC
Variable Interest Entity [Line Items]
Equity interest in joint venture	70.00%
Net income (loss) attributable to noncontrolling interest		$ 7,121								$ 7,524
Neogenyx Fuels LLC \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Net assets	$ 273,567
Noncontrolling interest in joint ventures	$ 241,799
Equity interest in joint venture	70.00%
Neogenyx Fuels LLC \| Subsidiaries
Variable Interest Entity [Line Items]
Net assets														$ 200,106
Neogenyx Fuels LLC \| HA Sustainable Infrastructure Capital, Inc.
Variable Interest Entity [Line Items]
Ownership percentage, noncontrolling owner	30.00%

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