Ameresco, Inc. Annual report [Section 13 and 15(d), not S-K Item 405]

Annual report [Section 13 and 15(d), not S-K Item 405]

Debt and Financing Lease Liabilities - Senior Secured Credit Facility - Revolver and Term Loans (Details)

Debt and Financing Lease Liabilities - Senior Secured Credit Facility - Revolver and Term Loans (Details)				12 Months Ended
	Jan. 23, 2025 USD ($)	Jun. 28, 2024 USD ($)	Apr. 10, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Apr. 15, 2024 USD ($)	Dec. 11, 2023	Dec. 10, 2023
Debt Instrument [Line Items]
Payments on long-term corporate debt financings				$ 127,000,000	$ 155,000,000	$ 52,813,000
Revolving Credit Facility
Debt Instrument [Line Items]
Minimum debt service coverage ratio				1.5	1.5
Additional borrowing capacity (up to)				$ 650,000,000	$ 650,000,000
Subordinated debt							$ 100,000,000
Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Additional borrowing capacity (up to)				100,000,000	100,000,000
Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Additional borrowing capacity (up to)				25,000,000	25,000,000
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 100,000,000	$ 200,000,000	$ 200,000,000
Increase in interest rate				0.25%	0.25%
Secured Debt \| Term loan A
Debt Instrument [Line Items]
Original principal amount				$ 75,000,000	$ 75,000,000
Senior Secured Credit Facility, Revolver And Term Loans \| Line of Credit
Debt Instrument [Line Items]
Original principal amount				495,000,000	495,000,000
Senior Secured Credit Facility, Revolver And Term Loans \| Line of Credit \| Revolving Credit Facility \| Debt Covenant, Period Five
Debt Instrument [Line Items]
Total funded debt to EBITDA covenant ratio, maximum								3.75	3.50
Delayed draw term loan A \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 220,000,000	$ 220,000,000
Senior Secured \| Secured Debt
Debt Instrument [Line Items]
Subordinated debt			100,000,000
Payments on long-term corporate debt financings		$ 15,000,000	5,000,000
Debt instrument, periodic payment, principal		$ 15,000,000	7,500,000
Senior Secured \| Secured Debt \| Subsequent Event
Debt Instrument [Line Items]
Payments of debt issuance costs	$ 2,000,000
Term Loan Due December 28, 2028 \| Secured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Payments on long-term corporate debt financings			225,000,000
Term Loan Due December 28, 2028 \| Secured Debt \| Term loan A
Debt Instrument [Line Items]
Payments on long-term corporate debt financings			$ 100,000,000