$AMRC
Ameresco, Inc. Stock $amrc

$amrc Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000148813921000036 Filed on March 02, 2021

Income Statement

Concept	2019 Q4	2018 Q4	2018
Revenue	$306.6M	$217.4M	$787.1M
YoY Change	41.05%	2.95%	9.76%
Cost Of Revenue	$259.0M	$168.2M	$613.5M
YoY Change	53.98%	-0.88%	7.07%
Gross Profit	$47.65M	$49.20M	$173.6M
YoY Change	-3.14%	18.67%	20.43%
Gross Profit Margin	15.54%	22.63%	22.06%
Selling, General & Admin	$28.90M	$29.40M	$114.5M
YoY Change	-1.7%	8.49%	7.83%
% of Gross Profit	60.65%	59.75%	65.96%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$10.31M	$8.490M	$29.15M
YoY Change	21.44%	27.48%	21.88%
% of Gross Profit	21.64%	17.26%	16.79%
Operating Expenses	$29.10M	$29.60M	$114.5M
YoY Change	-1.69%	8.03%	6.42%
Operating Profit	$18.55M	$19.60M	$59.10M
YoY Change	-5.34%	39.42%	61.53%
Interest Expense	-$3.700M	-$6.000M	$15.34M
YoY Change	-38.33%	130.77%	68.95%
% of Operating Profit	-19.94%	-30.61%	25.96%
Other Income/Expense, Net			-$16.71M
YoY Change			112.29%
Pretax Income	$14.80M	$13.60M	$46.54M
YoY Change	8.82%	19.3%	56.22%
Income Tax	-$5.700M	$2.900M	$4.813M
% Of Pretax Income	-38.51%	21.32%	10.34%
Net Earnings	$22.20M	$11.59M	$37.98M
YoY Change	91.52%	-51.31%	1.31%
Net Earnings / Revenue	7.24%	5.33%	4.83%
Basic Earnings Per Share	$0.47	$0.25	$0.83
Diluted Earnings Per Share	$0.46	$0.24	$0.81
COMMON SHARES
Basic Shares Outstanding	47.10M shares	46.11M shares	45.73M shares
Diluted Shares Outstanding	48.06M shares	47.33M shares	46.83M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments	$33.20M	$61.40M	$61.40M
YoY Change	-45.93%	152.67%	152.67%
Cash & Equivalents	$33.22M	$61.40M	$61.40M
Short-Term Investments
Other Short-Term Assets	$62.60M	$50.20M	$50.20M
YoY Change	24.7%	-65.62%	-65.62%
Inventory	$9.236M	$7.765M	$7.800M
Prepaid Expenses	$29.42M	$11.57M
Receivables	$315.1M	$186.3M	$186.3M
Other Receivables	$5.000M	$5.300M	$5.300M
Total Short-Term Assets	$425.2M	$311.0M	$311.0M
YoY Change	36.73%	8.32%	8.32%
LONG-TERM ASSETS
Property, Plant & Equipment	$10.10M	$6.985M	$466.9M
YoY Change	44.65%	31.72%	29.08%
Goodwill	$58.41M	$58.33M
YoY Change	0.14%	3.91%
Intangibles	$1.614M	$2.004M
YoY Change	-19.46%	-17.87%
Long-Term Investments
YoY Change
Other Assets	$11.79M	$29.39M	$29.40M
YoY Change	-59.9%	6.37%	6.52%
Total Long-Term Assets	$948.8M	$850.7M	$850.6M
YoY Change	11.54%	22.07%	22.05%
TOTAL ASSETS
Total Short-Term Assets	$425.2M	$311.0M	$311.0M
Total Long-Term Assets	$948.8M	$850.7M	$850.6M
Total Assets	$1.374B	$1.162B	$1.162B
YoY Change	18.28%	18.06%	18.05%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$202.4M	$134.3M	$134.3M
YoY Change	50.69%	-1.14%	-1.18%
Accrued Expenses	$31.36M	$35.95M	$35.90M
YoY Change	-12.77%	54.54%	54.08%
Deferred Revenue	$26.62M	$24.36M
YoY Change	9.26%	22.61%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$69.97M	$26.89M	$26.90M
YoY Change	160.2%	20.18%	20.09%
Total Short-Term Liabilities	$336.6M	$222.6M	$222.6M
YoY Change	51.21%	10.14%	10.14%
LONG-TERM LIABILITIES
Long-Term Debt	$266.2M	$219.2M	$219.2M
YoY Change	21.45%	26.51%	26.56%
Other Long-Term Liabilities	$29.58M	$29.21M	$323.9M
YoY Change	1.24%	55.76%	24.1%
Total Long-Term Liabilities	$295.8M	$248.4M	$543.1M
YoY Change	19.08%	29.37%	25.08%
TOTAL LIABILITIES
Total Short-Term Liabilities	$336.6M	$222.6M	$222.6M
Total Long-Term Liabilities	$295.8M	$248.4M	$543.1M
Total Liabilities	$632.4M	$471.0M	$784.8M
YoY Change	34.27%	19.5%	21.24%
SHAREHOLDERS EQUITY
Retained Earnings	$314.5M	$269.8M
YoY Change	16.55%	14.4%
Common Stock
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$11.78M	$11.64M
YoY Change	1.24%	18.77%
Treasury Stock Shares	2.101M shares	2.091M shares
Shareholders Equity	$428.9M	$376.9M	$376.9M
YoY Change
Total Liabilities & Shareholders Equity	$1.374B	$1.162B	$1.162B
YoY Change	18.28%	18.06%	18.05%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018
OPERATING ACTIVITIES
Net Income	$22.20M	$11.59M	$37.98M
YoY Change	91.52%	-51.31%	1.31%
Depreciation, Depletion And Amortization	$10.31M	$8.490M	$29.15M
YoY Change	21.44%	27.48%	21.88%
Cash From Operating Activities	-$75.56M	-$21.16M	-$53.20M
YoY Change	257.09%	-53.12%	-60.76%
INVESTING ACTIVITIES
Capital Expenditures	-$62.30M	-$82.60M	$3.943M
YoY Change	-24.58%	365.35%	38.3%
Acquisitions			$3.590M
YoY Change			49.02%
Other Investing Activities	$0.00	$59.10M	-$3.590M
YoY Change	-100.0%		-1070.27%
Cash From Investing Activities	-$62.29M	-$23.50M	-$133.2M
YoY Change	165.06%	32.39%	51.3%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$1.839M
YoY Change			-46.1%
Debt Paid & Issued, Net			$36.40M
YoY Change			-32.81%
Cash From Financing Activities	144.5M	45.72M	$224.5M
YoY Change	216.14%	-21.06%	-2.49%
NET CHANGE
Cash From Operating Activities	-75.56M	-21.16M	-$53.20M
Cash From Investing Activities	-62.29M	-23.50M	-$133.2M
Cash From Financing Activities	144.5M	45.72M	$224.5M
Net Change In Cash	6.690M	1.060M	$37.81M
YoY Change	531.13%	-121.33%	419.43%
FREE CASH FLOW
Cash From Operating Activities	-$75.56M	-$21.16M	-$53.20M
Capital Expenditures	-$62.30M	-$82.60M	$3.943M
Free Cash Flow	-$13.26M	$61.44M	-$57.14M
YoY Change	-121.58%	-324.32%	-58.72%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001488139
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
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CY2019Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	us-gaap:AssetsAbstract
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CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-34811
CY2020	dei	Entity Registrant Name EntityRegistrantName	Ameresco, Inc.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	04-3512838
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	111 Speen Street
CY2020	dei	Entity Address Address Line2 EntityAddressAddressLine2	Suite 410
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Framingham
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	MA
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	01701
CY2020	dei	City Area Code CityAreaCode	508
CY2020	dei	Local Phone Number LocalPhoneNumber	661-2200
CY2020	dei	Security12b Title Security12bTitle	Class A Common Stock,par value $0.0001 per share
CY2020	dei	Trading Symbol TradingSymbol	AMRC
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
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CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Accelerated Filer
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CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46831000	shares
CY2020	us-gaap	Profit Loss ProfitLoss	56922000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	40301000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	37577000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	1014000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	984000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	12000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-2784000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-2944000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-73000	USD
CY2020	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	1008000	USD
CY2019	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	1379000	USD
CY2018	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-250000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1776000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1565000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-323000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	55146000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	38736000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	37254000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	2870000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-4135000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-407000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	52276000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	42871000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	37661000	USD
CY2017Q4	us-gaap	Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests	10338000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	336620000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	6696000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1258000	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	501000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	1839000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	413000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-250000	USD
CY2018	amrc	Noncontrolling Interest Increase From Contributions From Noncontrolling Interest Holders NoncontrollingInterestIncreaseFromContributionsFromNoncontrollingInterestHolders	5198000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	410000	USD
CY2018	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	-407000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	37984000	USD
CY2018Q4	us-gaap	Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests	14719000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	376875000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	6742000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1620000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	675000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	144000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-2727000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	1379000	USD
CY2019	amrc	Noncontrolling Interest Increase From Contributions From Noncontrolling Interest Holders NoncontrollingInterestIncreaseFromContributionsFromNoncontrollingInterestHolders	21835000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	803000	USD
CY2019	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	-4135000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	44436000	USD
CY2019Q4	us-gaap	Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests	31616000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	428856000	USD
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	8995000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1933000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	880000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	6000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-2784000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	1008000	USD
CY2020	amrc	Noncontrolling Interest In Net Of Tax Equity Financing Fees Redeemable NoncontrollingInterestInNetOfTaxEquityFinancingFeesRedeemable	622000	USD
CY2020	amrc	Noncontrolling Interest Increase From Contributions From Noncontrolling Interest Holders NoncontrollingInterestIncreaseFromContributionsFromNoncontrollingInterestHolders	5777000	USD
CY2020	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	1534000	USD
CY2020	amrc	Temporary Equity Accretion Of Tax Equity Financing Fee TemporaryEquityAccretionOfTaxEquityFinancingFee	121000	USD
CY2020	amrc	Stockholders Equity Adjustment For Accretion Of Tax Equity Financing Fees StockholdersEquityAdjustmentForAccretionOfTaxEquityFinancingFees	121000	USD
CY2020	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	2870000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	54052000	USD
CY2020Q4	us-gaap	Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests	38850000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	492813000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	56922000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	40301000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	37577000	USD
CY2020	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	38039000	USD
CY2019	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	35543000	USD
CY2018	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	27305000	USD
CY2020	us-gaap	Depreciation Depreciation	3317000	USD
CY2019	us-gaap	Depreciation Depreciation	2987000	USD
CY2018	us-gaap	Depreciation Depreciation	2167000	USD
CY2020	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	2686000	USD
CY2019	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	2229000	USD
CY2018	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	2193000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	685000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	909000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1057000	USD
CY2020	amrc	Accretion Of Aro And Contingent Consideration AccretionOfAROAndContingentConsideration	93000	USD
CY2019	amrc	Accretion Of Aro And Contingent Consideration AccretionOfAROAndContingentConsideration	137000	USD
CY2018	amrc	Accretion Of Aro And Contingent Consideration AccretionOfAROAndContingentConsideration	0	USD
CY2020	amrc	Provisionfor Doubtful Accounts Including Retainage Accounts ProvisionforDoubtfulAccountsIncludingRetainageAccounts	282000	USD
CY2019	amrc	Provisionfor Doubtful Accounts Including Retainage Accounts ProvisionforDoubtfulAccountsIncludingRetainageAccounts	-216000	USD
CY2018	amrc	Provisionfor Doubtful Accounts Including Retainage Accounts ProvisionforDoubtfulAccountsIncludingRetainageAccounts	610000	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-2696000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-298000	USD
CY2020	amrc	Gain Loss On Disposition Of Variable Interest Entity GainLossOnDispositionOfVariableInterestEntity	0	USD
CY2019	amrc	Gain Loss On Disposition Of Variable Interest Entity GainLossOnDispositionOfVariableInterestEntity	2160000	USD
CY2018	amrc	Gain Loss On Disposition Of Variable Interest Entity GainLossOnDispositionOfVariableInterestEntity	0	USD
CY2020	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	705000	USD
CY2019	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	1068000	USD
CY2018	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	121000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	1933000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	1620000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	1258000	USD
CY2020	amrc	Deferred Income Tax Expense Benefit Excluding Effects Of Exchange Rates On Cash DeferredIncomeTaxExpenseBenefitExcludingEffectsOfExchangeRatesOnCash	3401000	USD
CY2019	amrc	Deferred Income Tax Expense Benefit Excluding Effects Of Exchange Rates On Cash DeferredIncomeTaxExpenseBenefitExcludingEffectsOfExchangeRatesOnCash	-3346000	USD
CY2018	amrc	Deferred Income Tax Expense Benefit Excluding Effects Of Exchange Rates On Cash DeferredIncomeTaxExpenseBenefitExcludingEffectsOfExchangeRatesOnCash	5517000	USD
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Unrealized ForeignCurrencyTransactionGainLossUnrealized	306000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Unrealized ForeignCurrencyTransactionGainLossUnrealized	130000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Unrealized ForeignCurrencyTransactionGainLossUnrealized	-1816000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	24178000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	8499000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-9772000	USD
CY2020	amrc	Increase Decrease In Accounts Receivable Retainage IncreaseDecreaseInAccountsReceivableRetainage	13113000	USD
CY2019	amrc	Increase Decrease In Accounts Receivable Retainage IncreaseDecreaseInAccountsReceivableRetainage	3370000	USD
CY2018	amrc	Increase Decrease In Accounts Receivable Retainage IncreaseDecreaseInAccountsReceivableRetainage	-3774000	USD
CY2020	us-gaap	Financing Receivable Significant Sales FinancingReceivableSignificantSales	227078000	USD
CY2019	us-gaap	Financing Receivable Significant Sales FinancingReceivableSignificantSales	188060000	USD
CY2018	us-gaap	Financing Receivable Significant Sales FinancingReceivableSignificantSales	155539000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-660000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	1471000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-373000	USD
CY2020	us-gaap	Increase Decrease In Contract With Customer Asset IncreaseDecreaseInContractWithCustomerAsset	-19474000	USD
CY2019	us-gaap	Increase Decrease In Contract With Customer Asset IncreaseDecreaseInContractWithCustomerAsset	106696000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Asset IncreaseDecreaseInContractWithCustomerAsset	-8015000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-517000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	18397000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-6763000	USD
CY2020	us-gaap	Increase Decrease In Construction Payables IncreaseDecreaseInConstructionPayables	-3085000	USD
CY2019	us-gaap	Increase Decrease In Construction Payables IncreaseDecreaseInConstructionPayables	8120000	USD
CY2018	us-gaap	Increase Decrease In Construction Payables IncreaseDecreaseInConstructionPayables	-8659000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-536000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-1056000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	3499000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	29047000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	43531000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	2938000	USD
CY2020	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	8042000	USD
CY2019	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	2662000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	2866000	USD
CY2020	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	1844000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-1625000	USD
CY2018	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-783000	USD
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-4292000	USD
CY2019	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-350000	USD
CY2018	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	1101000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-102583000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-196293000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-53201000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2211000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	6674000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	3943000	USD
CY2020	us-gaap	Payments To Acquire Other Productive Assets PaymentsToAcquireOtherProductiveAssets	180546000	USD
CY2019	us-gaap	Payments To Acquire Other Productive Assets PaymentsToAcquireOtherProductiveAssets	134738000	USD
CY2018	us-gaap	Payments To Acquire Other Productive Assets PaymentsToAcquireOtherProductiveAssets	125673000	USD
CY2020	amrc	Proceeds From Grant ProceedsFromGrant	1874000	USD
CY2019	amrc	Proceeds From Grant ProceedsFromGrant	784000	USD
CY2018	amrc	Proceeds From Grant ProceedsFromGrant	0	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	1294000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	3590000	USD
CY2020	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	132000	USD
CY2019	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	301000	USD
CY2018	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-181015000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-142223000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-133206000	USD
CY2020	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	5234000	USD
CY2019	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	1666000	USD
CY2018	us-gaap	Payments Of Financing Costs PaymentsOfFinancingCosts	4073000	USD
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	9875000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	7417000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	7197000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	6000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	144000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1839000	USD
CY2020	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	3000000	USD
CY2019	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	73347000	USD
CY2018	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	-900000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	116067000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	43883000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	88115000	USD
CY2020	amrc	Proceeds From Federal Espc Funding ProceedsFromFederalESPCFunding	248917000	USD
CY2019	amrc	Proceeds From Federal Espc Funding ProceedsFromFederalESPCFunding	199358000	USD
CY2018	amrc	Proceeds From Federal Espc Funding ProceedsFromFederalESPCFunding	158237000	USD
CY2020	amrc	Proceeds From Sale Of Investment Assets ProceedsFromSaleOfInvestmentAssets	1378000	USD
CY2019	amrc	Proceeds From Sale Of Investment Assets ProceedsFromSaleOfInvestmentAssets	2277000	USD
CY2018	amrc	Proceeds From Sale Of Investment Assets ProceedsFromSaleOfInvestmentAssets	4236000	USD
CY2020	amrc	Sale Leaseback Transaction Proceeds SaleLeasebackTransactionProceeds	0	USD
CY2019	amrc	Sale Leaseback Transaction Proceeds SaleLeasebackTransactionProceeds	0	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	98837000	USD
CY2018	amrc	Sale Leaseback Transaction Proceeds SaleLeasebackTransactionProceeds	5145000	USD
CY2020	us-gaap	Proceeds From Contributions From Affiliates ProceedsFromContributionsFromAffiliates	4805000	USD
CY2019	us-gaap	Proceeds From Contributions From Affiliates ProceedsFromContributionsFromAffiliates	21372000	USD
CY2018	us-gaap	Proceeds From Contributions From Affiliates ProceedsFromContributionsFromAffiliates	4788000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	73633000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	28425000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	36395000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	305169000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	317419000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	224511000	USD
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	447000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-295000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	21573000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-20650000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	37809000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	77264000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	97914000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	60105000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	77264000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	97914000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	20143000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	17467000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	15563000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	1465000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	3897000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	2257000	USD
CY2020	amrc	Noncashor Part Noncash Acquisition Financing Receivable Acquired NoncashorPartNoncashAcquisitionFinancingReceivableAcquired	54139000	USD
CY2019	amrc	Noncashor Part Noncash Acquisition Financing Receivable Acquired NoncashorPartNoncashAcquisitionFinancingReceivableAcquired	242519000	USD
CY2018	amrc	Noncashor Part Noncash Acquisition Financing Receivable Acquired NoncashorPartNoncashAcquisitionFinancingReceivableAcquired	101557000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	43807000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	35248000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	15005000	USD
CY2020	us-gaap	Debt Conversion Converted Instrument Amount1 DebtConversionConvertedInstrumentAmount1	0	USD
CY2019	us-gaap	Debt Conversion Converted Instrument Amount1 DebtConversionConvertedInstrumentAmount1	25000000	USD
CY2018	us-gaap	Debt Conversion Converted Instrument Amount1 DebtConversionConvertedInstrumentAmount1	25000000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	66422000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	33223000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	61397000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	22063000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	20006000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	16880000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	10352000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	24035000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	19637000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	98837000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	77264000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	97914000	USD
CY2020	us-gaap	Nature Of Operations NatureOfOperations	DESCRIPTION OF BUSINESS<div style="margin-bottom:9pt;margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Ameresco, Inc. (including its subsidiaries, the “Company,” “Ameresco”, “we,” “our,” or “us”) was organized as a Delaware corporation on April 25, 2000. We are a provider of energy efficiency solutions for facilities throughout North America and the United Kingdom. We provide solutions, both services and products, that enable our customers to reduce their energy consumption, lower their operating and maintenance costs and realize environmental benefits. Our comprehensive set of solutions includes upgrades to a facility’s energy infrastructure and the construction and operation of small-scale renewable energy plants. We also sell certain photovoltaic (“PV”) equipment worldwide and operate in the United States, Canada, and the United Kingdom.</span></div><div style="margin-bottom:9pt;margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">We are compensated through a variety of methods, including: 1) direct payments based on fee-for-services contracts (utilizing lump-sum or cost-plus pricing methodologies), 2) the sale of energy from our energy assets, and 3) direct payment for PV equipment and systems.</span></div>
CY2020Q4	amrc	Investment Funds Purchase Of Solar Energy Systems InvestmentFundsPurchaseOfSolarEnergySystems	5	fund
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-bottom:9pt;margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Changes in circumstances could cause actual results to differ materially from those estimates. The most significant estimates and assumptions used in these consolidated financial statements relate to management’s estimates of final construction contract profit in accordance with accounting for long-term contracts, allowance for credit losses, inventory reserves, realization of project development costs, leases, fair value of derivative financial instruments, accounting for business acquisitions, stock-based awards, impairment of goodwill and long-lived assets, asset retirement obligations (“AROs”), income taxes, self-insurance reserves, potential liability in conjunction with certain commitments and contingencies, and recognition of the investors’ share of net assets of certain subsidiaries as redeemable non-controlling interests.</span></div><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Self-insured Health Insurance</span></div><div style="margin-bottom:9pt;margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">We are self-insured for employee health insurance and the maximum exposure in fiscal year 2020 under the plan was $150 per covered participant, after which reinsurance takes effect. The liability for unpaid claims and associated expenses, including incurred but not reported claims, is determined by management and reflected in our consolidated balance sheets in accrued expenses and other current liabilities. The liability is calculated based on historical data, which considers both the frequency and settlement amount of claims. Our estimated accrual for this liability could be different than our ultimate obligation if variables such as the frequency or amount of future claims differ significantly from management’s assumptions.</span></div>
CY2020	amrc	Loss Contingency Self Insurance Maximum Exposure Per Participant LossContingencySelfInsuranceMaximumExposurePerParticipant	150000
CY2020Q4	amrc	Coronavirus Aid Relief And Economic Securities Cares Act Accrued Payroll Taxes Amount Due In2021 And2022 CoronavirusAidReliefAndEconomicSecuritiesCARESActAccruedPayrollTaxesAmountDueIn2021And2022	4532000	USD
CY2020	amrc	Coronavirus Aid Relief And Economic Securities Cares Act Tax Benefit Due To Net Operating Loss CoronavirusAidReliefAndEconomicSecuritiesCARESActTaxBenefitDueToNetOperatingLoss	2000000	USD
CY2020	amrc	Coronavirus Aid Relief And Economic Securities Cares Act Proceeds From Tax Refund CoronavirusAidReliefAndEconomicSecuritiesCARESActProceedsFromTaxRefund	1700000	USD
CY2020	amrc	Alternative Minimum Tax Cares Act AlternativeMinimumTaxCARESAct	3200000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	2260000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	2765000	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	3315000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	282000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	-216000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	610000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	276000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	289000	USD
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	1160000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	2266000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	2260000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	2765000	USD
CY2020	amrc	Contracts Receivable Retainage Allowancesand Reserves ContractsReceivableRetainageAllowancesandReserves	0	USD
CY2019	amrc	Contracts Receivable Retainage Allowancesand Reserves ContractsReceivableRetainageAllowancesandReserves	0	USD
CY2020Q4	amrc	Capitalized Project Development Costs Noncurrent CapitalizedProjectDevelopmentCostsNoncurrent	1543000	USD
CY2019Q4	amrc	Capitalized Project Development Costs Noncurrent CapitalizedProjectDevelopmentCostsNoncurrent	1080000	USD
CY2020	amrc	Grant Proceeds GrantProceeds	1874000	USD
CY2019	amrc	Grant Proceeds GrantProceeds	784000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	9143000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	8189000	USD
CY2018	us-gaap	Operating Leases Income Statement Lease Revenue OperatingLeasesIncomeStatementLeaseRevenue	7238000	USD
CY2020Q4	amrc	Long Term Debt Carrying Value In Excess Of Fair Value LongTermDebtCarryingValueInExcessOfFairValue	-5924000	USD
CY2020Q4	amrc	Number Of Joint Ventures NumberOfJointVentures	4	joint_venture
CY2020Q4	amrc	Investment Funds Purchase Of Solar Energy Systems InvestmentFundsPurchaseOfSolarEnergySystems	5	fund
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1032275000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	866933000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	787138000	USD
CY2020	amrc	Revenues Percentage Of Revenue Recognized Over Time RevenuesPercentageOfRevenueRecognizedOverTime	0.94
CY2019	amrc	Revenues Percentage Of Revenue Recognized Over Time RevenuesPercentageOfRevenueRecognizedOverTime	0.92
CY2018	amrc	Revenues Percentage Of Revenue Recognized Over Time RevenuesPercentageOfRevenueRecognizedOverTime	0.93
CY2020Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	125010000	USD
CY2019Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	95863000	USD
CY2019Q4	us-gaap	Receivables Long Term Contracts Or Programs ReceivablesLongTermContractsOrPrograms	16976000	USD
CY2020Q4	us-gaap	Receivables Long Term Contracts Or Programs ReceivablesLongTermContractsOrPrograms	30189000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	185960000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	202243000	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	40615000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	32178000	USD
CY2020	amrc	Contract With Customer Asset Revenue Recognized ContractWithCustomerAssetRevenueRecognized	644583000	USD
CY2020	us-gaap	Contract With Customer Asset Reclassified To Receivable ContractWithCustomerAssetReclassifiedToReceivable	618839000	USD
CY2020	amrc	Contract With Customer Liability Including New Contract Revenue Recognized ContractWithCustomerLiabilityIncludingNewContractRevenueRecognized	132622000	USD
CY2020	amrc	Contract With Customer Liability Billings ContractWithCustomerLiabilityBillings	140275000	USD
CY2019	amrc	Contract With Customer Asset Revenue Recognized ContractWithCustomerAssetRevenueRecognized	496733000	USD
CY2019	us-gaap	Contract With Customer Asset Reclassified To Receivable ContractWithCustomerAssetReclassifiedToReceivable	387815000	USD
CY2019	amrc	Contract With Customer Liability Including New Contract Revenue Recognized ContractWithCustomerLiabilityIncludingNewContractRevenueRecognized	113357000	USD
CY2019	amrc	Contract With Customer Liability Billings ContractWithCustomerLiabilityBillings	117577000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	2026770000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Percentage RevenueRemainingPerformanceObligationPercentage	0.33
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P12M
CY2020	amrc	Revenue From Contract With Customer Contract Term RevenueFromContractWithCustomerContractTerm	P25Y
CY2019Q4	us-gaap	Capitalized Contract Cost Gross CapitalizedContractCostGross	1735000	USD
CY2020Q4	us-gaap	Capitalized Contract Cost Gross CapitalizedContractCostGross	1735000	USD
CY2020	amrc	Capitalized Contract Cost Project Development Costs CapitalizedContractCostProjectDevelopmentCosts	12790000	USD
CY2019	amrc	Capitalized Contract Cost Project Development Costs CapitalizedContractCostProjectDevelopmentCosts	35172000	USD
CY2018	amrc	Capitalized Contract Cost Project Development Costs CapitalizedContractCostProjectDevelopmentCosts	15672000	USD
CY2020	us-gaap	Capitalized Contract Cost Impairment Loss CapitalizedContractCostImpairmentLoss	0	USD
CY2019	us-gaap	Capitalized Contract Cost Impairment Loss CapitalizedContractCostImpairmentLoss	0	USD
CY2018Q4	us-gaap	Goodwill Goodwill	58332000	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	337000	USD
CY2019	us-gaap	Goodwill Purchase Accounting Adjustments GoodwillPurchaseAccountingAdjustments	-630000	USD
CY2019	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	375000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	58414000	USD
CY2020	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	300000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	58714000	USD
CY2019Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	1016000	USD
CY2020Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	1016000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	27240000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	26966000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	26313000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	25352000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	927000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1614000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	685000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	909000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1057000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Before Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization	24118000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Before Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization	42536000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization	15136000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization	32432000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	8982000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	10104000	USD
CY2020	us-gaap	Depreciation Depreciation	3317000	USD
CY2019	us-gaap	Depreciation Depreciation	2987000	USD
CY2018	us-gaap	Depreciation Depreciation	2167000	USD
CY2020	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	38039000	USD
CY2019	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	35543000	USD
CY2018	us-gaap	Utilities Operating Expense Depreciation And Amortization UtilitiesOperatingExpenseDepreciationAndAmortization	27305000	USD
CY2020	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	4341000	USD
CY2019	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	2966000	USD
CY2018	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	3817000	USD
CY2020	us-gaap	Tangible Asset Impairment Charges TangibleAssetImpairmentCharges	1028000	USD
CY2020Q4	amrc	Number Of Espc Projects NumberOfESPCProjects	3	project
CY2019Q4	amrc	Number Of Espc Projects NumberOfESPCProjects	3	project
CY2020	amrc	Business Combination Number Of Projects Acquired BusinessCombinationNumberOfProjectsAcquired	1	project
CY2019	amrc	Business Combination Number Of Projects Acquired BusinessCombinationNumberOfProjectsAcquired	9	project
CY2020	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	1251000	USD
CY2019	us-gaap	Business Combination Consideration Transferred1 BusinessCombinationConsiderationTransferred1	8519000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	0	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	6059000	USD
CY2020	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	2460000	USD
CY2020Q4	amrc	Business Combination Contingent Consideration Liability For Previously Closed Projects BusinessCombinationContingentConsiderationLiabilityForPreviouslyClosedProjects	1446000	USD
CY2019Q4	amrc	Business Combination Contingent Consideration Liability For Previously Closed Projects BusinessCombinationContingentConsiderationLiabilityForPreviouslyClosedProjects	1178000	USD
CY2020	amrc	Business Combination Definitive Agreements Number Of Projects To Be Acquired BusinessCombinationDefinitiveAgreementsNumberOfProjectsToBeAcquired	8	project
CY2020	amrc	Business Combination Definitive Agreements Consideration To Be Transferred BusinessCombinationDefinitiveAgreementsConsiderationToBeTransferred	10242000	USD
CY2020	us-gaap	Payments To Acquire Businesses Gross PaymentsToAcquireBusinessesGross	0	USD
CY2020	amrc	Lessee Operating Lease Number Of Renewal Options LesseeOperatingLeaseNumberOfRenewalOptions	1	renewal_option
CY2020Q4	us-gaap	Asset Retirement Obligation Legally Restricted Assets Fair Value AssetRetirementObligationLegallyRestrictedAssetsFairValue	1468000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation Legally Restricted Assets Fair Value AssetRetirementObligationLegallyRestrictedAssetsFairValue	852000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	86000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	160000	USD
CY2020Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	1561000	USD
CY2019Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	781000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	1647000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	941000	USD
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	93000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	44000	USD
CY2018	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	0	USD
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	8891000	USD
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	8179000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	6463000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	39151000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	32791000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	6106000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	5802000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	35300000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	29101000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	41406000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	34903000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P12Y
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P11Y
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.059
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.063
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	34005000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	36134000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	4273000	USD
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	4997000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	19227000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	23500000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	23500000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	28497000	USD
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P16Y
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P17Y
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.1194
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.118
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	7970000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	7460000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	2129000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	2129000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	3019000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	3630000	USD
CY2020	amrc	Financing Lease Cost FinancingLeaseCost	5148000	USD
CY2019	amrc	Financing Lease Cost FinancingLeaseCost	5759000	USD
CY2020	us-gaap	Lease Cost LeaseCost	13118000	USD
CY2019	us-gaap	Lease Cost LeaseCost	13219000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	7600000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	7300000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	12158000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	6203000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	8231000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	6792000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	7274000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	5178000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	5964000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	3676000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4955000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	2565000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3981000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	2213000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	28956000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	21867000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	59361000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	42291000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	17955000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	18791000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	41406000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	23500000	USD
CY2020	amrc	Sale Leaseback Transaction Net Amortization Expense SaleLeasebackTransactionNetAmortizationExpense	228000	USD
CY2019	amrc	Sale Leaseback Transaction Net Amortization Expense SaleLeasebackTransactionNetAmortizationExpense	230000	USD
CY2018	amrc	Sale Leaseback Transaction Net Amortization Expense SaleLeasebackTransactionNetAmortizationExpense	-109000	USD
CY2020Q1	amrc	Maximum Combined Funding Amount Sale Leaseback Transactions MaximumCombinedFundingAmountSaleLeasebackTransactions	150000000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	23500000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	28497000	USD
CY2020Q4	amrc	Long Term Debt And Capital Lease Obligations Gross LongTermDebtAndCapitalLeaseObligationsGross	391761000	USD
CY2019Q4	amrc	Long Term Debt And Capital Lease Obligations Gross LongTermDebtAndCapitalLeaseObligationsGross	345748000	USD
CY2020Q4	amrc	Long Term Debt And Finance Lease Obligations Current LongTermDebtAndFinanceLeaseObligationsCurrent	69362000	USD
CY2019Q4	amrc	Long Term Debt And Finance Lease Obligations Current LongTermDebtAndFinanceLeaseObligationsCurrent	69969000	USD
CY2020Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	10725000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	9598000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	311674000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	266181000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	18791000	USD
CY2019Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	22015000	USD
CY2020	amrc	Debt Instrument Covenant Consolidated Debt Service Coverage Ratio Minimum DebtInstrumentCovenantConsolidatedDebtServiceCoverageRatioMinimum	1.20
CY2020Q4	amrc	Long Term Debt And Finance Leases Maturity Year One LongTermDebtAndFinanceLeasesMaturityYearOne	69362000	USD
CY2020Q4	amrc	Long Term Debt And Finance Leases Maturity Year Two LongTermDebtAndFinanceLeasesMaturityYearTwo	26327000	USD
CY2020Q4	amrc	Long Term Debt And Finance Leases Maturity Year Three LongTermDebtAndFinanceLeasesMaturityYearThree	40311000	USD
CY2020Q4	amrc	Long Term Debt And Finance Leases Maturity Year Four LongTermDebtAndFinanceLeasesMaturityYearFour	116391000	USD
CY2020Q4	amrc	Long Term Debt And Finance Leases Maturity Year Five LongTermDebtAndFinanceLeasesMaturityYearFive	48092000	USD
CY2020Q4	amrc	Long Term Debt And Finance Leases Maturity After Year Five LongTermDebtAndFinanceLeasesMaturityAfterYearFive	91278000	USD
CY2020Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	10725000	USD
CY2020Q4	amrc	Long Term Debt And Finance Leases LongTermDebtAndFinanceLeases	381036000	USD
CY2019Q2	amrc	Debt Instrument Covenant Total Funded Debt To Ebitda Ratio Maximum DebtInstrumentCovenantTotalFundedDebtToEBITDARatioMaximum	3.00
CY2019Q2	amrc	Debt Instrument Covenant Total Funded Debt To Ebitda Ratio Minimum DebtInstrumentCovenantTotalFundedDebtToEBITDARatioMinimum	3.25
CY2020Q4	us-gaap	Line Of Credit LineOfCredit	110270000	USD
CY2019Q4	us-gaap	Line Of Credit LineOfCredit	111997000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	491000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	639000	USD
CY2020Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	11916000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	52595000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	34700000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	46542000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	3833000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	1853000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	-4152000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	56428000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	36553000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	42390000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-4566000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	109000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-1888000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1522000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	474000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1176000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	298000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	-1000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	30000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-2746000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	582000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-682000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	3655000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-4794000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	2662000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2207000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	202000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2530000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-3610000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	262000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	303000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2252000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4330000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	5495000	USD
CY2020Q4	amrc	Deferred Tax Assets Interest Limitation DeferredTaxAssetsInterestLimitation	0	USD
CY2019Q4	amrc	Deferred Tax Assets Interest Limitation DeferredTaxAssetsInterestLimitation	5148000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-494000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3748000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4813000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	2485000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	1745000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	3861000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	2739000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	15621000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	9398000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	14435000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	14355000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	2587000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	1604000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	42046000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	35939000	USD
CY2020Q4	amrc	Deferred Tax Assets Deferred Revenue DeferredTaxAssetsDeferredRevenue	1270000	USD
CY2019Q4	amrc	Deferred Tax Assets Deferred Revenue DeferredTaxAssetsDeferredRevenue	1635000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	8902000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	82305000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	72563000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	3877000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	8583000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	78428000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	63980000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	66694000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	51579000	USD
CY2020Q4	amrc	Deferred Tax Liabilities Contract Refinancing DeferredTaxLiabilitiesContractRefinancing	284000	USD
CY2019Q4	amrc	Deferred Tax Liabilities Contract Refinancing DeferredTaxLiabilitiesContractRefinancing	328000	USD
CY2020Q4	amrc	Deferred Tax Liabilities Outside Basis Difference DeferredTaxLiabilitiesOutsideBasisDifference	10886000	USD
CY2019Q4	amrc	Deferred Tax Liabilities Outside Basis Difference DeferredTaxLiabilitiesOutsideBasisDifference	8488000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	80791000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	64095000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	2363000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	115000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	36553000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	42390000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	11850000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	7676000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	3877000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	8583000	USD
CY2020Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	93464000	USD
CY2019	amrc	Effective Income Tax Rate Reconciliation Deduction Section179 Amount EffectiveIncomeTaxRateReconciliationDeductionSection179Amount	29700000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	56428000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	2257000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	2140000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	3071000	USD
CY2020	amrc	Income Tax Reconciliation Nondeductible Expense Deferred Rate Change Net IncomeTaxReconciliationNondeductibleExpenseDeferredRateChangeNet	-29000	USD
CY2019	amrc	Income Tax Reconciliation Nondeductible Expense Deferred Rate Change Net IncomeTaxReconciliationNondeductibleExpenseDeferredRateChangeNet	-53000	USD
CY2018	amrc	Income Tax Reconciliation Nondeductible Expense Deferred Rate Change Net IncomeTaxReconciliationNondeductibleExpenseDeferredRateChangeNet	174000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Meals And Entertainment IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment	987000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Meals And Entertainment IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment	150000	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Meals And Entertainment IncomeTaxReconciliationNondeductibleExpenseMealsAndEntertainment	982000	USD
CY2020	amrc	Effective Income Tax Rate Reconciliation Reservefor Uncertain Tax Positions Amount EffectiveIncomeTaxRateReconciliationReserveforUncertainTaxPositionsAmount	-124000	USD
CY2019	amrc	Effective Income Tax Rate Reconciliation Reservefor Uncertain Tax Positions Amount EffectiveIncomeTaxRateReconciliationReserveforUncertainTaxPositionsAmount	-925000	USD
CY2018	amrc	Effective Income Tax Rate Reconciliation Reservefor Uncertain Tax Positions Amount EffectiveIncomeTaxRateReconciliationReserveforUncertainTaxPositionsAmount	879000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-2922000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-169000	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-441000	USD
CY2020	amrc	Income Tax Reconciliation Nondeductible Expense Energy Efficiency Preferences IncomeTaxReconciliationNondeductibleExpenseEnergyEfficiencyPreferences	-8595000	USD
CY2019	amrc	Income Tax Reconciliation Nondeductible Expense Energy Efficiency Preferences IncomeTaxReconciliationNondeductibleExpenseEnergyEfficiencyPreferences	-12699000	USD
CY2018	amrc	Income Tax Reconciliation Nondeductible Expense Energy Efficiency Preferences IncomeTaxReconciliationNondeductibleExpenseEnergyEfficiencyPreferences	-8636000	USD
CY2020	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	160000	USD
CY2019	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	56000	USD
CY2018	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-41000	USD
CY2020	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	767000	USD
CY2019	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	-1101000	USD
CY2018	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	-70000	USD
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-4308000	USD
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	205000	USD
CY2018	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	641000	USD
CY2020	amrc	Income Tax Reconciliation Nondeductible Expense Miscellaneous IncomeTaxReconciliationNondeductibleExpenseMiscellaneous	997000	USD
CY2019	amrc	Income Tax Reconciliation Nondeductible Expense Miscellaneous IncomeTaxReconciliationNondeductibleExpenseMiscellaneous	-1230000	USD
CY2018	amrc	Income Tax Reconciliation Nondeductible Expense Miscellaneous IncomeTaxReconciliationNondeductibleExpenseMiscellaneous	-788000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-494000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3748000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4813000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.040
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.059
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.072
CY2020	amrc	Effective Income Tax Rate Reconciliation State Impact Of Deferred Rate Change Net EffectiveIncomeTaxRateReconciliationStateImpactOfDeferredRateChangeNet	-0.001
CY2019	amrc	Effective Income Tax Rate Reconciliation State Impact Of Deferred Rate Change Net EffectiveIncomeTaxRateReconciliationStateImpactOfDeferredRateChangeNet	-0.001
CY2018	amrc	Effective Income Tax Rate Reconciliation State Impact Of Deferred Rate Change Net EffectiveIncomeTaxRateReconciliationStateImpactOfDeferredRateChangeNet	0.004
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Meals And Entertainment EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment	0.017
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Meals And Entertainment EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment	0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Meals And Entertainment EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment	0.023
CY2020	amrc	Effective Income Tax Rate Reconciliation Reservefor Uncertain Tax Positions Percent EffectiveIncomeTaxRateReconciliationReserveforUncertainTaxPositionsPercent	-0.002
CY2019	amrc	Effective Income Tax Rate Reconciliation Reservefor Uncertain Tax Positions Percent EffectiveIncomeTaxRateReconciliationReserveforUncertainTaxPositionsPercent	-0.025
CY2018	amrc	Effective Income Tax Rate Reconciliation Reservefor Uncertain Tax Positions Percent EffectiveIncomeTaxRateReconciliationReserveforUncertainTaxPositionsPercent	0.021
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.052
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.005
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.010
CY2020	amrc	Effective Income Tax Rate Reconciliation Energy Efficiency Preferences EffectiveIncomeTaxRateReconciliationEnergyEfficiencyPreferences	-0.152
CY2019	amrc	Effective Income Tax Rate Reconciliation Energy Efficiency Preferences EffectiveIncomeTaxRateReconciliationEnergyEfficiencyPreferences	-0.347
CY2018	amrc	Effective Income Tax Rate Reconciliation Energy Efficiency Preferences EffectiveIncomeTaxRateReconciliationEnergyEfficiencyPreferences	-0.204
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.003
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.002
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	100000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.001
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	0.014
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	-0.030
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	-0.002
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.076
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.006
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.015
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.018
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.036
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.018
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.009
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.103
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.114
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	400000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1600000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	100000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	1200000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	600000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	400000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	190000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	80000	USD
CY2020	amrc	Earningswith No Repatriation Tax EarningswithNoRepatriationTax	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	19000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	-50000	USD
CY2020Q4	amrc	Investment Funds Purchase Of Solar Energy Systems InvestmentFundsPurchaseOfSolarEnergySystems	5	fund
CY2019Q1	amrc	Joint Venture Number Of Employees JointVentureNumberOfEmployees	0	employee
CY2019Q1	us-gaap	Payments To Acquire Interest In Joint Venture PaymentsToAcquireInterestInJointVenture	1506000	USD
CY2019Q1	amrc	Joint Venture Ownership Percentage JointVentureOwnershipPercentage	0.50
CY2020Q4	amrc	Equity Method Investments Venture Investments Investment Position Net Asset Liability EquityMethodInvestmentsVentureInvestmentsInvestmentPositionNetAssetLiability	1189000	USD
CY2019Q4	amrc	Equity Method Investments Venture Investments Investment Position Net Asset Liability EquityMethodInvestmentsVentureInvestmentsInvestmentPositionNetAssetLiability	1292000	USD
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-225000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-183000	USD
CY2020	amrc	Variable Interest Entity Investor Contributed Capital Balance Percentage VariableInterestEntityInvestorContributedCapitalBalancePercentage	0.07
CY2020	amrc	Variable Interest Entity Remaining Investor Contributed Capital Balance Percentage VariableInterestEntityRemainingInvestorContributedCapitalBalancePercentage	0.05
CY2020	amrc	Variable Interest Entity Remaining Investor Contributed Capital Balance Percentage VariableInterestEntityRemainingInvestorContributedCapitalBalancePercentage	0.05
CY2020	us-gaap	Net Income Loss NetIncomeLoss	54052000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	44436000	USD
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1199000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.13
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.95
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.83
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.10
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.93
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.81
CY2018	us-gaap	Net Income Loss NetIncomeLoss	37984000	USD
CY2020	amrc	Adjustment For Accretion Of Tax Equity Financing Fees AdjustmentForAccretionOfTaxEquityFinancingFees	121000	USD
CY2019	amrc	Adjustment For Accretion Of Tax Equity Financing Fees AdjustmentForAccretionOfTaxEquityFinancingFees	0	USD
CY2018	amrc	Adjustment For Accretion Of Tax Equity Financing Fees AdjustmentForAccretionOfTaxEquityFinancingFees	0	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	53931000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	44436000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	37984000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	47702000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	46586000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	45729000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1304000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1188000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1102000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49006000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	47774000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	46831000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	806000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	692000	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3834000	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	7.367
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	518000	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	10.878
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	909000	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	7.367
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	87000	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	4.726
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod	51000	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice	9.146
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3305000	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	8.050
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	1330000	shares
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1	P8Y4M24D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber	1912000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice	15.568
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	14.026
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	916000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	7.362
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	210000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	8.070
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod	4000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice	9.904
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3505000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	10.524
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	406000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	25.668
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	946000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	9.491
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	49000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	13.251
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod	0	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice	0
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2916000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	12.919
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y1M6D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	114659000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	1004000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	7.877
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P4Y7M6D
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	44555000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue	70103000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	19762000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	7154000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	5588000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	8995000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	6742000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	6696000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	11.52
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	6.33
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	5.20
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1933000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1620000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1258000	USD
CY2019Q4	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2292000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	6200000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	5998000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	5469000	USD
CY2020Q4	us-gaap	Other Commitment OtherCommitment	137000	USD
CY2020Q4	us-gaap	Noncurrent Assets NoncurrentAssets	738360000	USD
CY2019Q4	us-gaap	Noncurrent Assets NoncurrentAssets	589565000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1032275000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	866933000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	787138000	USD
CY2020	us-gaap	Gain Loss On Derivative Instruments Net Pretax GainLossOnDerivativeInstrumentsNetPretax	705000	USD
CY2019	us-gaap	Gain Loss On Derivative Instruments Net Pretax GainLossOnDerivativeInstrumentsNetPretax	1068000	USD
CY2018	us-gaap	Gain Loss On Derivative Instruments Net Pretax GainLossOnDerivativeInstrumentsNetPretax	121000	USD
CY2020	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-15422000	USD
CY2019	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-13841000	USD
CY2018	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-13132000	USD
CY2020	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	2686000	USD
CY2019	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	2229000	USD
CY2018	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	1894000	USD
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	481000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-59000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-1804000	USD
CY2020	amrc	Government Incentives GovernmentIncentives	1851000	USD
CY2019	amrc	Government Incentives GovernmentIncentives	0	USD
CY2018	amrc	Government Incentives GovernmentIncentives	0	USD
CY2020	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-15071000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-15061000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-16709000	USD
CY2020Q4	amrc	Deferred Financing Costs Amortization Next Twelve Months DeferredFinancingCostsAmortizationNextTwelveMonths	2782000	USD
CY2020Q4	amrc	Deferred Financing Costs Amortization Year Two DeferredFinancingCostsAmortizationYearTwo	1734000	USD
CY2020Q4	amrc	Deferred Financing Costs Amortization Year Three DeferredFinancingCostsAmortizationYearThree	1458000	USD
CY2020Q4	amrc	Deferred Financing Costs Amortization Year Four DeferredFinancingCostsAmortizationYearFour	1200000	USD
CY2020Q4	amrc	Deferred Financing Costs Amortization Year Five DeferredFinancingCostsAmortizationYearFive	843000	USD
CY2020Q4	amrc	Business Combination Contingent Consideration Arrangements Rangeof Outcomes Probability Base Case BusinessCombinationContingentConsiderationArrangementsRangeofOutcomesProbabilityBaseCase	0.50
CY2020Q4	amrc	Business Combination Contingent Consideration Arrangements Rangeof Outcomes Probability Low BusinessCombinationContingentConsiderationArrangementsRangeofOutcomesProbabilityLow	0.50
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	678000	USD
CY2018Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	599000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings	79000	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	678000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	678000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1032275000	USD
CY2020	us-gaap	Interest Income Operating InterestIncomeOperating	250000	USD
CY2020	us-gaap	Interest Expense InterestExpense	12891000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	40137000	USD
CY2020	amrc	Income Before Income Taxes And Unallocated Corporate Expenses IncomeBeforeIncomeTaxesAndUnallocatedCorporateExpenses	96616000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	866933000	USD
CY2019	us-gaap	Interest Income Operating InterestIncomeOperating	524000	USD
CY2019	us-gaap	Interest Expense InterestExpense	12622000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	37709000	USD
CY2019	amrc	Income Before Income Taxes And Unallocated Corporate Expenses IncomeBeforeIncomeTaxesAndUnallocatedCorporateExpenses	70742000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	787138000	USD
CY2018	us-gaap	Interest Income Operating InterestIncomeOperating	282000	USD
CY2018	us-gaap	Interest Expense InterestExpense	15344000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	29148000	USD
CY2018	amrc	Income Before Income Taxes And Unallocated Corporate Expenses IncomeBeforeIncomeTaxesAndUnallocatedCorporateExpenses	72805000	USD

Files In Submission

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$AMRC
Ameresco, Inc. Stock $amrc

2019 Q4 Form 10-K Financial Statement

#000148813921000036 Filed on March 02, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMRC Ameresco, Inc. Stock $amrc

2019 Q4 Form 10-K Financial Statement

#000148813921000036 Filed on March 02, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMRC
Ameresco, Inc. Stock $amrc