Ameresco, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Subsequent Events (Narrative) (Details)

Subsequent Events (Narrative) (Details) (Holdings IV [Member], Subsequent Event [Member], USD $) In Millions, unless otherwise specified	0 Months Ended
	Oct. 19, 2012 project entity
Subsequent Event [Line Items]
Number of renewable energy project companies owned	18
Number of renewable energy projects owned	22
Number of renewable energy projects, operating	16
Number of renewable energy projects, in construction	6
Line of Credit [Member] \| Construction-To-Term Loan Credit Facility [Member]
Subsequent Event [Line Items]
Number of renewable energy projects owned	20
Credit and guaranty agreement, maximum borrowing capacity	47.2
Draw down of construction loans	33.5
Line of Credit [Member] \| Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Portion of proceeds used to pay down revolving credit facility	13.5

- Definition

The cash outflow to pay off an obligation from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity.

+ References + Details