Ameresco, Inc. Annual report pursuant to Section 13 and 15(d)

Variable Interest Entities and Equity Method Investments - Additional Information (Details)

v3.22.0.1

Variable Interest Entities and Equity Method Investments - Additional Information (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2019 USD ($) employee	Dec. 31, 2021 USD ($) Joint_venture fund	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Variable Interest Entity [Line Items]
Investment funds \| fund		5
Number of investment funds \| fund		4
Joint venture, number of employees \| employee	0
Contributions to joint venture	$ 1,506
Interest in joint venture	50.00%
Number of joint ventures \| Joint_venture		3
Proceeds from sale of equity method investment		$ 1,672	$ 0	$ 0
Gain from sale of equity method investment		575	0	2,160
Contributions to equity investment		9,000	$ 132	301
Other Assets
Variable Interest Entity [Line Items]
Equity method investment				$ 1,361
Operating Income (Loss)
Variable Interest Entity [Line Items]
VIE, impact of deconsolidation	$ 2,160
Selling, general and administrative expense
Variable Interest Entity [Line Items]
Gain from sale of equity method investment		$ 571

- Definition

Investment Funds, Purchase Of Solar Energy Systems

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- Definition

Joint Venture, Number Of Employees

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- Definition

Joint Venture, Ownership Percentage

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- Definition

Number Of Investment Funds

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- Definition

Number Of Joint Ventures

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- Definition

Variable Interest Entity, Impact Of Deconsolidation

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- Definition

Amount of gain (loss) on sale or disposal of an equity method investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
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-Section 45
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- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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