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

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Revenue from Contracts with Customers - Additional Information (Details)

v3.10.0.1

Revenue from Contracts with Customers - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Increase (decrease) in retained earnings	$ 258,213,000	$ 258,213,000	$ 231,390,000	$ 235,844,000
Contract with customer, liability, noncurrent	7,017,000	7,017,000
Contract with customer, asset, reclassified to receivable		398,917,000
Contract with customer, asset, revenue recognized		344,768,000
Contract with customer, liability, revenue recognized		116,892,000
Contract with customer, liability, billings		119,961,000
Revenue, remaining performance obligation	$ 1,757,000,000	$ 1,757,000,000
Revenue, remaining performance obligation, percentage	26.00%	26.00%
Capitalized commission costs			927,000
Capitalized contract cost, impairment loss		$ 0
Capitalized contract cost, project development costs	$ 7,561,000	$ 13,571,000
Minimum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivable retainage percentage	5.00%	5.00%
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivable retainage percentage	10.00%	10.00%
Effect of Change Higher/(Lower) \| Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Increase (decrease) in retained earnings	$ (6,897,000)	$ (6,897,000)	$ (4,454,000)

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Amount, before accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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