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

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

v3.26.1

VARIABLE INTEREST ENTITIES AND EQUITY METHOD INVESTMENTS - Additional Information (Details) - USD ($) $ in Thousands		6 Months Ended
	May 12, 2026	Jun. 30, 2026	Jun. 30, 2025
Variable Interest Entity [Line Items]
Payments of financing costs		$ 2,506	$ 6,763
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
Contributions to joint venture	233,800
HA Sustainable Infrastructure Capital, Inc.
Variable Interest Entity [Line Items]
Remaining interest in joint venture	$ 166,200
Neogenyx Fuels LLC \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Equity interest in joint venture	70.00%
Neogenyx Fuels LLC \| HA Sustainable Infrastructure Capital, Inc.
Variable Interest Entity [Line Items]
Ownership percentage, noncontrolling owner	30.00%

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