Quarterly report [Sections 13 or 15(d)]

SUBSEQUENT EVENT (Details)

v3.26.1
SUBSEQUENT EVENT (Details) - Subsequent Event - USD ($)
$ in Millions
3 Months Ended
Jun. 30, 2026
May 04, 2026
JV Investor    
Subsequent Event [Line Items]    
JV Investor investment in Joint Venture   $ 400
Ameresco and AMRC Biogas HoldCo    
Subsequent Event [Line Items]    
Equity interest in joint venture 70.00%  
Ownership percentage, noncontrolling owner   30.00%
Ameresco and AMRC Biogas HoldCo | JV Investor    
Subsequent Event [Line Items]    
Contributions to joint venture $ 100  
Joint venture, repayment of assumed debt $ 58