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

Quarterly report [Sections 13 or 15(d)]

DEBT AND FINANCING LEASE LIABILITIES - Additional Information (Details)

DEBT AND FINANCING LEASE LIABILITIES - Additional Information (Details)					2 Months Ended	3 Months Ended	6 Months Ended
	Jun. 27, 2025 USD ($)	May 27, 2025 USD ($)	Apr. 30, 2025 USD ($)	Jan. 23, 2025 USD ($)	Jun. 27, 2025 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2025 USD ($) project	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
Repayments of secured debt							$ 15,500,000	$ 67,500,000
Make-whole Provision April 2045 \| Other liabilities \| Not Designated
Debt Instrument [Line Items]
Liability derivatives, fair value			$ 3,040,000
Make-whole Provisions May 2038 \| Other liabilities \| Not Designated
Debt Instrument [Line Items]
Liability derivatives, fair value		$ 347,000
Senior secured corporate term loans \| Secured Debt
Debt Instrument [Line Items]
Repayments of secured debt				$ 13,000,000
Long-term debt, gross						$ 97,500,000	$ 97,500,000		$ 13,000,000
Term Loan A \| Secured Debt
Debt Instrument [Line Items]
Fixed interest rate, percentage						6.85%	6.85%
Senior Secured Credit Facility \| Secured Debt
Debt Instrument [Line Items]
Debt issuance costs						$ 2,345,000	$ 2,345,000
Term Loan Due May 27,2028 \| Line of Credit
Debt Instrument [Line Items]
Repayments of debt		8,273,000
Senior Secured Notes, Due September 2045 \| Senior Notes
Debt Instrument [Line Items]
Fixed interest rate, percentage			6.72%
Debt issuance costs			$ 3,126,000
Proceeds from issuance of senior long-term debt	$ 10,291,000		$ 67,708,000		$ 78,000,000
Debt instrument, term			20 years
Original principal amount			$ 300,000,000
Investment tax credit, prepayment amount							$ 30,000,000
Term Loan Due June 2025 \| Line of Credit
Debt Instrument [Line Items]
Repayments of debt		$ 31,086,000
August 2018 Long Term Finance Liability \| Solar Photovoltaic Projects
Debt Instrument [Line Items]
Solar PV projects sold \| project							5
Cash proceeds from sale-leaseback of energy assets							$ 18,946,000
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, periodic payment				$ 1,250,000
Minimum debt service coverage ratio				1.5
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Fixed interest rate, percentage						7.48%	7.48%
Proceeds used to repay revolving credit facility				$ 180,000,000
Maximum borrowing capacity				$ 100,000,000
Revolving Credit Facility \| Senior Secured Credit Facility \| Line of Credit \| Debt Covenant, Period Five
Debt Instrument [Line Items]
Total funded debt to EBITDA covenant ratio				3.5
Revolving Credit Facility \| Term Loan Due December 28, 2028 \| Secured Debt
Debt Instrument [Line Items]
Repayments of secured debt				$ 225,000,000
Revolving Credit Facility \| Construction Credit Facility, Due December2027 \| Line of Credit
Debt Instrument [Line Items]
Fixed interest rate, percentage						8.32%	8.32%
Repayments of debt							$ 60,213,000
Long-term debt						$ 390,574,000	390,574,000
Proceeds to pay off the construction credit facility							$ 138,655,000
Revolving Credit Facility \| Construction Credit Facility, Due March 2026 \| Line of Credit
Debt Instrument [Line Items]
Fixed interest rate, percentage						5.93%	5.93%
Long-term debt, gross						$ 19,205,000	$ 19,205,000
Funds available for borrowing						80,795,000	80,795,000
Revolving Credit Facility \| Minimum \| Senior secured corporate term loans \| Line of Credit
Debt Instrument [Line Items]
Unused capacity, commitment fee percentage				0.25%
Revolving Credit Facility \| Minimum \| Base Rate \| Senior secured corporate term loans \| Line of Credit
Debt Instrument [Line Items]
Interest rate				0.75%
Revolving Credit Facility \| Minimum \| Secured Overnight Financing Rate (SOFR) \| Senior secured corporate term loans \| Line of Credit
Debt Instrument [Line Items]
Interest rate				1.75%
Revolving Credit Facility \| Maximum \| Senior secured corporate term loans \| Line of Credit
Debt Instrument [Line Items]
Unused capacity, commitment fee percentage				0.375%
Revolving Credit Facility \| Maximum \| Base Rate \| Senior secured corporate term loans \| Line of Credit
Debt Instrument [Line Items]
Interest rate				1.75%
Revolving Credit Facility \| Maximum \| Secured Overnight Financing Rate (SOFR) \| Senior secured corporate term loans \| Line of Credit
Debt Instrument [Line Items]
Interest rate				2.75%
Line of Credit \| Term Loan Due May 27,2028 \| Line of Credit
Debt Instrument [Line Items]
Fixed interest rate, percentage		6.62%
Debt issuance costs		$ 402,000
Proceeds used to repay revolving credit facility		8,273,000
Original principal amount		$ 12,221,000
Line of Credit \| Term Loan Due June 2025 \| Line of Credit
Debt Instrument [Line Items]
Fixed interest rate, percentage		6.87%
Term Loan \| Term Loan Due December 28, 2028 \| Secured Debt
Debt Instrument [Line Items]
Repayments of secured debt				$ 100,000,000
Financing Facility \| Financing Facility, Due August 2039
Debt Instrument [Line Items]
Fixed interest rate, percentage		6.70%
Financing Facility \| Financing Facility, Due August 2039 \| Line of Credit
Debt Instrument [Line Items]
Repayments of loan						7,000,000
Long-term debt						$ 345,173,000	$ 345,173,000