Ameresco (AMRC) 10-Q 5 May 20 2020 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2020	May 01, 2020
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	001-34811
Entity Registrant Name	Ameresco, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	04-3512838
Entity Address, Address Line One	111 Speen Street
Entity Address, Address Line Two	Suite 410
Entity Address, City or Town	Framingham
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01701
City Area Code	508
Local Phone Number	661-2200
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Trading Symbol	AMRC
Security Exchange Name	NYSE
Entity Central Index Key	0001488139
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Amendment Flag	false
Common Class A
Entity Information [Line Items]
Title of 12(b) Security	Class A Common Stock, $0.0001 par value per share
Entity Common Stock, Shares Outstanding (in shares)		29,567,741
Common Class B
Entity Information [Line Items]
Title of 12(b) Security	Class B Common Stock, $0.0001 par value per share
Entity Common Stock, Shares Outstanding (in shares)		18,000,000

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands		Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	[1]	$ 40,351	$ 33,223
Restricted cash	[1]	15,012	20,006
Accounts receivable, net of allowance of $2,587 and $2,765, respectively	[1]	110,742	95,863
Accounts receivable retainage, net		21,265	16,976
Costs and estimated earnings in excess of billings	[1]	189,566	202,243
Inventory, net		9,229	9,236
Prepaid expenses and other current assets	[1]	28,052	29,424
Income tax receivable		7,135	5,033
Project development costs		16,740	13,188
Total current assets	[1]	438,092	425,192
Federal ESPC receivable		239,156	230,616
Property and equipment, net	[1]	9,952	10,104
Energy assets, net	[1]	596,492	579,461
Deferred income taxes, net		2,470	0
Goodwill		57,741	58,414
Intangible assets, net		1,408	1,614
Operating lease assets	[1]	32,444	32,791
Other assets	[1]	35,828	35,821
Total assets	[1]	1,413,583	1,374,013
Current liabilities:
Current portions of long-term debt and financing lease liabilities	[1]	69,282	69,969
Accounts payable	[1]	182,354	202,416
Accrued expenses and other current liabilities	[1]	32,528	31,356
Current portions of operating lease liabilities	[1]	5,360	5,802
Billings in excess of cost and estimated earnings		25,350	26,618
Income taxes payable		1,205	486
Total current liabilities	[1]	316,079	336,647
Long-term debt and financing lease liabilities, net current portions and deferred financing fees	[1]	285,553	266,181
Federal ESPC liabilities		276,177	245,037
Deferred income taxes, net	[1]	0	115
Deferred grant income		6,682	6,885
Long-term portions of operating lease liabilities, net of current portion	[1]	29,104	29,101
Other liabilities	[1]	35,872	29,575
Commitments and contingencies (Note 9)
Redeemable non-controlling interests		31,939	31,616
Stockholders’ equity:
Preferred stock, $0.0001 par value, 5,000,000 shares authorized, no shares issued and outstanding at March 31, 2020 and December 31, 2019		0	0
Additional paid-in capital		136,591	133,688
Retained earnings		320,660	314,459
Accumulated other comprehensive loss, net		(13,291)	(7,514)
Treasury stock, at cost, 2,101,795 shares at March 31, 2020 and 2,101,340 shares at December 31, 2019		(11,788)	(11,782)
Total stockholders’ equity		432,177	428,856
Total liabilities, redeemable non-controlling interests and stockholders’ equity		1,413,583	1,374,013
Common Class A
Stockholders’ equity:
Common stock		3	3
Common Class B
Stockholders’ equity:
Common stock		2	2
Variable Interest Entity, Primary Beneficiary
Current assets:
Total current assets		8,272	7,017
Total assets		163,019	158,912
Current liabilities:
Total current liabilities		$ 6,633	$ 6,563
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounts Receivable, Allowance for Credit Loss, Current	$ 2,120	$ 2,260
Preferred stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common Class A
Common stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	31,611,956	31,331,345
Common stock, shares outstanding (in shares)	29,510,161	29,230,005
Treasury stock, shares (in shares)	2,101,795	2,101,340
Common Class B
Common stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	144,000,000	144,000,000
Common stock, shares issued (in shares)	18,000,000	18,000,000
Common stock, shares outstanding (in shares)	18,000,000	18,000,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenues	$ 212,413	$ 150,112
Cost of revenues	173,967	117,480
Gross profit	38,446	32,632
Selling, general and administrative expenses	28,924	26,083
Operating income	9,522	6,549
Other expenses, net	5,389	3,421
Income before (benefit) provision for income taxes	4,133	3,128
Income tax (benefit) provision	(2,503)	257
Net income	6,636	2,871
Net loss (income) attributable to redeemable non-controlling interests	(435)	1,276
Net income attributable to common shareholders	$ 6,201	$ 4,147
Net income per share attributable to common shareholders:
Basic (in usd per share)	$ 0.13	$ 0.09
Diluted (in usd per share)	$ 0.13	$ 0.09
Weighted average common shares outstanding:
Basic (in shares)	47,384	46,293
Diluted (in shares)	48,497	47,654

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 6,636	$ 2,871
Other comprehensive income (loss):
Unrealized (loss) gain from interest rate hedges, net of tax (provision) benefit	(3,465)	(1,142)
Foreign currency translation adjustments	(2,312)	606
Total other comprehensive (loss) income	(5,777)	(536)
Comprehensive income	859	2,335
Comprehensive loss (income) attributable to redeemable non-controlling interests	(435)	1,276
Comprehensive income attributable to common shareholders	424	3,611
Unrealized (loss) gain from interest rate hedges, tax benefit (provision)	$ (1,187)	$ (325)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Unrealized (loss) gain from interest rate hedges, tax benefit (provision)	$ (1,187)	$ (325)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Changes in Redeemable Non-Controlling Interests and Stockholders' Equity - USD ($) $ in Thousands	Total	Common Class A	Common Class B	Common StockCommon Class A	Common StockCommon Class B	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Redeemable non-controlling interests, beginning balance at Dec. 31, 2018	$ 14,719
Increase (Decrease) in Temporary Equity [Roll Forward]
Distributions to redeemable non-controlling interests	(102)
Temporary Equity, Net Income	(1,276)
Redeemable non-controlling interests, ending balance at Mar. 31, 2019	13,341
Beginning balance (in shares) at Dec. 31, 2018				28,275,506	18,000,000				2,091,040
Beginning balance at Dec. 31, 2018	376,875			$ 3	$ 2	$ 124,651	$ 269,806	$ (5,949)	$ (11,638)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)				61,920
Exercise of stock options	649					649
Stock-based compensation expense	385					385
Open market purchase of common shares (in shares)									0
Unrealized loss from interest rate hedge, net	(925)							(925)
Foreign currency translation adjustments	606							606
Net (loss) income	4,147						4,147
Ending balance (in shares) at Mar. 31, 2019				28,337,426	18,000,000				2,091,040
Ending balance at Mar. 31, 2019	381,737			$ 3	$ 2	125,685	274,170	(6,485)	$ (11,638)
Redeemable non-controlling interests, beginning balance at Dec. 31, 2019	31,616
Increase (Decrease) in Temporary Equity [Roll Forward]
Distributions to redeemable non-controlling interests	(112)
Temporary Equity, Net Income	435
Redeemable non-controlling interests, ending balance at Mar. 31, 2020	31,939
Beginning balance (in shares) at Dec. 31, 2019		29,230,005	18,000,000	29,230,005	18,000,000				2,101,340
Beginning balance at Dec. 31, 2019	428,856			$ 3	$ 2	133,688	314,459	(7,514)	$ (11,782)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)				280,611
Exercise of stock options	2,474					2,474
Stock-based compensation expense	429					429
Open market purchase of common shares (in shares)				455					455
Open market purchase of common shares	(6)								$ (6)
Unrealized loss from interest rate hedge, net	(3,465)							(3,465)
Foreign currency translation adjustments	(2,312)							(2,312)
Net (loss) income	6,201						6,201
Ending balance (in shares) at Mar. 31, 2020		29,510,161	18,000,000	29,510,161	18,000,000				2,101,795
Ending balance at Mar. 31, 2020	$ 432,177			$ 3	$ 2	$ 136,591	$ 320,660	$ (13,291)	$ (11,788)

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net income	$ 6,636	$ 2,871
Adjustments to reconcile net income to cash flows from operating activities:
Depreciation of energy assets	9,299	8,407
Depreciation of property and equipment	833	619
Amortization of debt discount and deferred financing fees	660	693
Amortization of intangible assets	179	213
Accretion of ARO and contingent consideration	21	51
Provision for bad debts	49	77
Gain on deconsolidation of VIE	0	(2,160)
Net gain from derivatives	(223)	(723)
Stock-based compensation expense	429	385
Deferred income taxes	(1,217)	0
Unrealized foreign exchange loss	212	(59)
Changes in operating assets and liabilities:
Accounts receivable	(14,161)	4,718
Accounts receivable retainage	(4,445)	(1,201)
Federal ESPC receivable	(39,946)	(26,986)
Inventory, net	7	(1,165)
Costs and estimated earnings in excess of billings	12,181	(1,027)
Prepaid expenses and other current assets	1,233	(2,939)
Project development costs	(3,224)	(3,688)
Other assets	8	549
Accounts payable, accrued expenses and other current liabilities	(17,241)	(40,976)
Billings in excess of cost and estimated earnings	(956)	809
Other liabilities	(586)	(228)
Income taxes payable, net	(1,388)	3,666
Cash flows from operating activities	(51,640)	(58,094)
Cash flows from investing activities:
Purchases of property and equipment	(724)	(1,287)
Purchases of energy assets	(28,497)	(23,334)
Acquisitions, net of cash received	0	(1,279)
Contributions to equity investment	(127)	(192)
Cash flows from investing activities	(29,348)	(26,092)
Cash flows from financing activities:
Payments of financing fees	(155)	0
Proceeds from exercises of options and ESPP	2,473	649
Repurchase of common stock	(6)	0
Proceeds from senior secured credit facility, net	31,000	11,373
Proceeds from Federal ESPC projects	61,198	39,598
Proceeds for energy assets from Federal ESPC	1,541	1,732
Distributions to redeemable non-controlling interests, net	(103)	(103)
Payments on long-term debt	(12,019)	(5,716)
Cash flows from financing activities	83,929	47,533
Effect of exchange rate changes on cash	(509)	140
Net increase (decrease) in cash, cash equivalents, and restricted cash	2,432	(36,513)
Cash, cash equivalents, and restricted cash, beginning of period	77,264	97,914
Cash, cash equivalents, and restricted cash, end of period	79,696	61,401
Supplemental disclosures of cash flow information:
Cash paid for interest	4,917	3,391
Cash paid for income taxes	183	197
Non-cash Federal ESPC settlement	29,297	5,629
Accrued purchases of energy assets	34,308	16,247
Reconciliation of cash, cash equivalents and restricted cash
Total cash and cash equivalents, and restricted cash	$ 79,696	$ 61,401

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	BASIS OF PRESENTATION The accompanying condensed consolidated financial statements of Ameresco, Inc. (including its subsidiaries, the “Company”) are unaudited, pursuant to certain rules and regulations of the Securities and Exchange Commission, and include, in the opinion of the Company, normal recurring adjustments necessary for a fair presentation in conformity with accounting principles generally accepted in the United States (“GAAP”) of the results for the periods indicated. The results of operations for the three months ended March 31, 2020 are not necessarily indicative of results which may be expected for the full year. The December 31, 2019 consolidated balance sheet data was derived from audited financial statements, but certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted. The interim condensed consolidated financial statements, and notes thereto, should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2019, and notes thereto, included in the Company’s annual report on Form 10-K for the year ended December 31, 2019 filed with the Securities and Exchange Commission on March 4, 2020. SIGNIFICANT RISKS AND UNCERTAINTIES In March 2020, the World Health Organization categorized Coronavirus Disease 2019 (“COVID-19”) as a pandemic, and the President of the United States declared the COVID-19 outbreak a national emergency. The Company’s condensed consolidated financial statements reflect estimates and assumptions made by management that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and reported amounts of revenue and expenses during the reporting periods presented. The Company considered the impact of COVID-19 on the assumptions and estimates used and determined that there were no material adverse impact on the Company’s first quarter 2020 results of operations. The severity of the impact of the COVID-19 pandemic on the Company's business will depend on a number of factors, including, but not limited to, the duration and severity of the pandemic and the extent and severity of the impact on the Company's customers, all of which are uncertain and cannot be predicted. The Company's future results of operations and liquidity could be adversely impacted by delays in payments of outstanding receivable amounts beyond normal payment terms, delays in obtaining signed customer contracts for awarded projects, supply chain disruptions and uncertain demand. As of the date of issuance of these condensed consolidated financial statements, the extent to which the COVID-19 pandemic may materially impact the Company's financial condition, liquidity, or results of operations is uncertain.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES The accounting policies of the Company are set forth in Note 2 to the consolidated financial statements contained in the Company’s 2019 annual report on Form 10-K . The Company includes herein certain updates to those policies. Accounts Receivable and allowance for Credit Losses Accounts receivable are stated at the amount management expects to collect from outstanding balances. Effective January 1, 2020, the Company adopted ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13) prospectively. This ASU replaces the incurred loss impairment model with an expected credit loss impairment model for financial instruments, including trade receivables. The amendment requires entities to consider forward-looking information to estimate expected credit losses, resulting in earlier recognition of losses for receivables that are current or not yet due, which were not considered under the previous accounting guidance. The Company performed an assessment of its allowance for credit losses based upon historical experience, management’s evaluation of outstanding accounts receivable, consideration of its customers’ financial conditions and current macroeconomic and market conditions and determined that no adjustment was required to retained earnings upon adoption. The Company’s methodology to estimate the allowance for credit losses includes quarterly assessments of historical bad debt write off experience, current economic and market conditions, management’s evaluation of outstanding accounts receivable, and the Company’s forecasts. Due to the short-term nature of its receivables, the estimate of credit losses is primarily based on aged accounts receivable balances and the financial condition of customers. In addition, specific allowance amounts are established to record the appropriate provision for customers that have a higher probability of default. Bad debts are written off against the allowance when identified. As part of its assessment, the Company also considered the current and expected future economic and market conditions due to the COVID-19 pandemic and determined that the estimate of credit losses was not significantly impacted as of March 31, 2020. Changes in the allowance for credit losses for the three months ended March 31, 2020 and 2019 are as follows: March 31, 2020 March 31, 2019 Allowance for credit loss, beginning of period $ 2,260 $ 2,765 Charges to costs and expenses, net 49 77 Account write-offs and other (189) (29) Allowance for credit loss, end of period $ 2,120 $ 2,813 Recent Accounting Pronouncements Fair Value Measurement In August 2018, the FASB issued ASU 2018-13 Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement, which modifies the disclosure requirements on fair value measurements. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company adopted this guidance as of January 1, 2020 and the adoption did not have a material impact on the Company’s consolidated financial statements. Consolidations In October 2018, the FASB issued ASU No. 2018-17, Consolidation (Topic 810), Targeted Improvements to Related Party Guidance for Variable Interest Entities, which aligns the evaluation of whether a decision maker's fee is a variable interest with the guidance in the primary beneficiary test by requiring the decision maker to consider an indirect interest in a VIE held by related party under common control on a proportionate basis. The new standard is effective interim and annual periods beginning after December 15, 2019, with early adoption permitted. The Company adopted this guidance as of January 1, 2020 and the adoption did not have an impact on the Company’s consolidated financial statements. Credit Losses In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), and a subsequent amendment to the initial guidance, ASU 2018-19 Codification Improvements to Topic 326, Financial Instruments—Credit Losses (collectively, Topic 326). Topic 326 requires measurement and recognition of expected credit losses for financial assets held, which include, but are not limited to, trade and other receivables. The new standard is effective for fiscal years beginning after December 15, 2019, The Company adopted this guidance as of January 1, 2020 and the adoption did not have a material impact on the Company’s consolidated financial statements. In April 2019, the FASB issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments – Credit Losses, Topic 815, Derivatives, and Hedging, and Topic 825, Financial Instruments. The improvements to Topic 815, among other things, clarifies some areas around partial-term fair value hedges, interest rate risk, the amortization of fair value hedge basis adjustments and their disclosure, and some clarification of matters related to the transitioning to ASU. 2017-12, which was adopted by the Company during the year ended December 31, 2018. The improvements to Topic 326 clarifies certain aspects surrounding accounting for credit losses in connection with the Company’s receivables. These include that the Company should include anticipated recoveries in its calculation of credit losses. For those that have already adopted ASU No. 2017-12, the new standard is effective the first annual period beginning after the issuance date of ASU No. 2019-04, or as of January 1, 2020 for the Company, with early adoption permitted. The Company adopted this guidance as of January 1, 2020 and the adoption did not have a material impact on the Company’s consolidated financial statements. Income Taxes In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes, eliminates certain exceptions within ASC 740, Income Taxes, and clarifies certain aspects of the current guidance to promote consistency among reporting entities. ASU 2019-12 is effective for the Company for the fiscal year beginning after December 15, 2020. The Company is currently evaluating the impacts of the provisions of ASU 2019-12 on its consolidated financial statements and disclosures. Others In March 2020, the FASB issued ASU 2020-04 Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. ASU 2020-04 provides optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. Companies can apply the ASU immediately, however the guidance will only be available until December 31, 2022. The Company is currently evaluating the impact that adopting this new accounting standard will have on its condensed consolidated financial statements and related disclosures.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	3 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	REVENUE FROM CONTRACTS WITH CUSTOMERS Disaggregation of Revenue The following table provides information about disaggregated revenue by line of business, reportable segments, and geographical region for the three months ended March 31, 2020 and 2019. US Regions U.S. Federal Canada Non-Solar DG All Other Total Line of Business Three Months Ended March 31, 2020 Project revenue $ 71,493 $ 56,114 $ 8,864 $ 2,371 $ 5,587 $ 144,429 O&M revenue 4,352 11,626 9 2,015 60 18,062 Energy assets 8,554 719 663 17,986 300 28,222 Other 328 286 1,856 352 18,878 21,700 Total revenues $ 84,727 $ 68,745 $ 11,392 $ 22,724 $ 24,825 $ 212,413 Three Months Ended March 31, 2019 Project revenue $ 45,704 $ 32,353 $ 5,234 $ 1,074 $ 3,067 $ 87,432 O&M revenue 3,318 9,858 — 2,035 — 15,211 Energy assets 6,021 643 320 17,699 302 24,985 Other 554 203 1,594 422 19,711 22,484 Total revenues $ 55,597 $ 43,057 $ 7,148 $ 21,230 $ 23,080 $ 150,112 US Regions U.S. Federal Canada Non-Solar DG All Other Total Geographical Regions Three Months Ended March 31, 2020 United States $ 84,727 $ 68,745 $ 896 $ 22,724 $ 18,847 $ 195,939 Canada — — 10,496 — 57 10,553 Other — — — — 5,921 5,921 Total revenues $ 84,727 $ 68,745 $ 11,392 $ 22,724 $ 24,825 $ 212,413 Three Months Ended March 31, 2019 United States $ 55,597 $ 43,057 $ 702 $ 21,230 $ 18,647 $ 139,233 Canada — — 6,446 — 65 6,511 Other — — — — 4,368 4,368 Total revenues $ 55,597 $ 43,057 $ 7,148 $ 21,230 $ 23,080 $ 150,112 For the three months ended March 31, 2020 and 2019, approximately 91% and 89%, respectively, of revenue is recognized over time, and the remainder is for products and services transferred at a point in time. Contract Balances The following table provides information about receivables, contract assets and contract liabilities from contracts with customers: March 31, 2020 December 31, 2019 Accounts receivable, net $ 110,742 $ 95,863 Accounts receivable retainage, net 21,265 16,976 Contract Assets: Costs and estimated earnings in excess of billings 189,566 202,243 Contract Liabilities: Billings in excess of cost and estimated earnings 30,670 32,178 March 31, 2019 December 31, 2018 Accounts receivable, net $ 81,896 $ 85,985 Accounts receivable retainage, net 14,762 13,516 Contract Assets: Costs and estimated earnings in excess of billings 92,264 86,842 Contract Liabilities: Billings in excess of cost and estimated earnings 31,483 30,706 Accounts receivable retainage represents amounts due from customers, but where payments are withheld contractually until certain construction milestones are met. Amounts retained typically range from 5% to 10% of the total invoice. The Company classifies as a current asset those retainages that are expected to be billed in the next twelve months. Unbilled revenue, presented as costs and estimated earnings in excess of billings, represent amounts earned and billable that were not invoiced at the end of the fiscal period. Contract assets represent the Company’s rights to consideration in exchange for services transferred to a customer that have not been billed as of the reporting date. The Company’s rights to consideration are generally unconditional at the time its performance obligations are satisfied. At the inception of a contract, the Company expects the period between when it satisfies its performance obligations, and when the customer pays for the services, will be one year or less. As such, the Company has elected to apply the practical expedient which allows the Company to not adjust the promised amount of consideration for the effects of a significant financing component, when a financing component is present. When the Company receives consideration, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a sales contract, the Company records deferred revenue, which represents a contract liability. Such deferred revenue typically results from billings in excess of costs incurred and advanced payments received on project contracts. As of March 31, 2020 and December 31, 2019, the Company classified $5,320 and $5,560, respectively, as a non-current liability, included in other liabilities on the condensed consolidated balance sheets, for those performance obligations expected to be completed beyond the next twelve months. The decrease in contract assets for the three months ended March 31, 2020 was primarily due to billings of $152,612, offset in part by revenue recognized of approximately $137,596. The decrease in contract liabilities was primarily driven by recognition of revenue as performance obligations were satisfied exceeding increases from the receipt of advance payments from customers and related billings. For the three months ended March 31, 2020, the Company recognized revenue of $19,552 that was previously included in the beginning balance of contract liabilities and billed customers $15,651. Changes in contract liabilities are also driven by reclassifications to or from contract assets as a result of timing of customer payments. The increase in contract assets for the three months ended March 31, 2019 was primarily due to revenue recognized of $90,344, offset in part by billings of approximately $90,895. The increase in contract liabilities was primarily driven by the receipt of advance payment from customers, and related billings, exceeding reductions from recognition of revenue as performance obligations were satisfied. For the three months ended March 31, 2019, the Company recognized revenue of $24,095 that was previously included in the beginning balance of contract liabilities, and billed customers $18,929. Changes in contract liabilities are also driven by reclassifications to or from contract assets as a result of timing of customer payments. Contracts are often modified for a change in scope or other requirements. The Company considers contract modifications to exist when the modification either creates new or changes the existing enforceable rights and obligations. Most of the Company’s contract modifications are for goods or services that are not distinct from the existing performance obligations. The effect of a contract modification on the transaction price, and the measure of progress for the performance obligation to which it relates, is recognized as an adjustment to revenue (either as an increase or decrease) on a cumulative catchup basis. Performance Obligations A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. Performance obligations are satisfied as of a point in time or over time and are supported by contracts with customers. For most of the Company’s contracts, there are multiple promises of goods or services. Typically, the Company provides a significant service of integrating a complex set of tasks and components such as design, engineering, construction management, and equipment procurement for a project contract. The bundle of goods and services are provided to deliver one output for which the customer has contracted. In these cases, the Company considers the bundle of goods and services to be a single performance obligation. The Company may also promise to provide distinct goods or services within a contract, such as a project contract for installation of energy conservation measures and post-installation O&M services. In these cases the Company separates the contract into more than one performance obligation. If a contract is separated into more than one performance obligation, the Company allocates the total transaction price to each performance obligation in an amount based on the estimated relative standalone selling prices of the promised goods or services underlying each performance obligation. Backlog - The Company’s remaining performance obligations (hereafter referred to as “backlog”) represent the unrecognized revenue value of the Company’s contract commitments. The Company’s backlog may vary significantly each reporting period based on the timing of major new contract commitments and the backlog may fluctuate with currency movements. In addition, our customers have the right, under some circumstances, to terminate contracts or defer the timing of the Company’s services and their payments to the Company. At March 31, 2020, the Company had backlog of approximately $2,181,643. Approximately 26% of our March 31, 2020 backlog is anticipated to be recognized as revenue in the next twelve months and the remaining, thereafter. The Company has applied the practical expedient for certain revenue streams to exclude the value of remaining performance obligations for (i) contracts with an original expected term of one year or less or (ii) contracts for which the Company recognizes revenue in proportion to the amount it has the right to invoice for services performed. Contract Acquisition Costs The Company accounts for certain acquisition costs over the life of the contract, consisting primarily of commissions when paid. Commission costs are incurred commencing at contract signing. Commission costs are allocated across all performance obligations and deferred and amortized over the contract term on a progress toward completion basis. As of March 31, 2020 and December 31, 2019, included in other assets in the accompanying condensed consolidated balance sheets, were $1,735 and $1,735, respectively, of capitalized commission costs related to contracts that were not completed. For contracts that have a duration of less than one year, the Company follows a practical expedient and expenses these costs when incurred. During the three months ended March 31, 2020 and 2019, the amortization of commission costs related to contracts was not material and has been included in the accompanying condensed consolidated statements of income. The Company capitalizes costs incurred related to the development of projects prior to contract signing as it is partial fulfillment of its performance obligations. Capitalized project development costs include only those costs incurred in connection with the development of energy projects, primarily direct labor, interest costs, outside contractor services, consulting fees, legal fees and travel, if incurred after a point in time where the realization of related revenue becomes probable. Project development costs incurred prior to the probable realization of revenue are expensed as incurred. The Company classifies as a current asset those project development efforts that are expected to proceed to construction activity in the twelve months that follow. The Company periodically reviews these balances and writes off any amounts where the realization of the related revenue is no longer probable. Project development costs of $697 and $217 were included in other long-term assets as of March 31, 2020 and December 31, 2019, respectively. During the three months ended March 31, 2020 and 2019, $1,635 and $2,777, respectively, of project development costs were recognized in the condensed consolidated statements of income on projects that converted to customer contracts. No impairment charges in connection with the Company’s commission costs or project development costs were recorded during the three months ended March 31, 2020 and 2019.

Business Acquisitions and Relat

Business Acquisitions and Related Transactions	3 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Business Acquisitions and Related Transactions	BUSINESS ACQUISITIONS AND RELATED TRANSACTIONS The Company accounts for acquisitions using the acquisition method in accordance with ASC 805, Business Combinations. The purchase price for each has been allocated to the net assets based on their estimated fair values at the date of each acquisition as set forth in the table below. The excess purchase price over the estimated fair value of the net assets, which are calculated using level 3 inputs per the fair value hierarchy as defined in Note 10, acquired has been recorded as goodwill. Intangible assets, if identified, have been recorded and are being amortized over periods ranging from one fifteen Determining the fair value of certain assets and liabilities assumed is judgmental in nature and often involves the use of significant estimates and assumptions. Certain amounts below are provisional based on our best estimates using information available as of the reporting date. The Company is waiting for information to become available to finalize its valuation of certain elements of these transactions. Specifically, the assigned values for energy assets, intangibles, and goodwill are provisional in nature and subject to change upon the completion of the final valuation of such elements. During the three months ended March 31, 2020, the Company did not complete any acquisitions. The results of the acquired assets since the dates of the acquisitions have been included in the Company’s operations as presented in the accompanying condensed consolidated statements of income, condensed consolidated statements of comprehensive income and condensed consolidated statements of cash flows.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	GOODWILL AND INTANGIBLE ASSETS The changes in the carrying value of goodwill attributable to each reportable segment are as follows: U.S. Regions U.S. Federal Canada Non-solar DG Other Total Balance, December 31, 2019 $ 26,705 $ 3,981 $ 3,369 $ — $ 24,359 $ 58,414 Currency effects — — (274) — (399) (673) Balance, March 31, 2020 $ 26,705 $ 3,981 $ 3,095 $ — $ 23,960 $ 57,741 Accumulated Goodwill Impairment Balance, December 31, 2019 $ — $ — $ (1,016) $ — $ — $ (1,016) Balance, March 31, 2020 $ — $ — $ (1,016) $ — $ — $ (1,016) The Company performs its annual goodwill impairment testing in the fourth quarter of each year, or more frequently if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of a reporting unit below its carrying amount. During the Company’s annual goodwill impairment testing in 2019, all reporting units had fair values that exceeded their carrying values by at least 15%. If the Company believes that one or more indicators of impairment have occurred, then the Company will perform an impairment test. The Company has the option to perform a qualitative assessment (commonly referred to as "step zero" test) to determine whether further quantitative analysis for impairment of goodwill and indefinite-lived intangible assets is necessary. The qualitative assessment includes a review of macroeconomic conditions, industry and market considerations, internal cost factors, and the Company’s own overall financial and share price performance, among other factors. If, after assessing the totality of events or circumstances the Company determines that it is not more-likely-than-not that the fair value of a reporting unit is less than its carrying amount, the Company does not need to perform a quantitative analysis. Upon assessment, the Company concluded it was not more likely than not that the fair value of the reporting units were less than the carrying value of the reporting units as of March 31, 2020. The Company will monitor future results and will perform a test if indicators trigger an impairment review. At this time, the Company has not deemed the impact that the current macroeconomic environment surrounding the COVID-19 pandemic has or is expected to have on the business to be a triggering event for impairment purposes. Separable intangible assets that are not deemed to have indefinite lives are amortized over their useful lives. The Company annually assesses whether a change in the life over which the Company’s assets are amortized is necessary, or more frequently if events or circumstances warrant. Acquired intangible assets other than goodwill that are subject to amortization include customer contracts, customer relationships, non-compete agreements, technology and trade names. Customer contracts are amortized ratably over the period of the acquired customer contracts ranging in periods from approximately one five four fifteen The gross carrying amount and accumulated amortization of intangible assets are as follows: As of March 31, As of December 31, 2020 2019 Gross Carrying Amount Customer contracts $ 7,749 $ 7,904 Customer relationships 12,449 12,749 Non-compete agreements 2,995 3,037 Technology 2,691 2,732 Trade names 539 544 26,423 26,966 Accumulated Amortization Customer contracts 7,711 7,844 Customer relationships 11,112 11,236 Non-compete agreements 2,995 3,037 Technology 2,669 2,704 Trade names 528 531 25,015 25,352 Intangible assets, net $ 1,408 $ 1,614

Energy Assets

Energy Assets	3 Months Ended
	Mar. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Energy Assets	ENERGY ASSETS Energy assets consist of the following: March 31, December 31, 2020 2019 Energy assets $ 793,215 $ 767,331 Less - accumulated depreciation and amortization (196,723) (187,870) Energy assets, net $ 596,492 $ 579,461 Included in energy assets are financing lease assets and accumulated depreciation of financing lease assets. Financing lease assets consist of the following: March 31, December 31, 2020 2019 Financing lease assets $ 42,402 $ 42,402 Less - accumulated depreciation and amortization (6,800) (6,268) Financing lease assets, net $ 35,602 $ 36,134 Depreciation and amortization expense on the above energy assets, net of deferred grant amortization, for the three months ended March 31, 2020 and 2019 was $9,299 and $8,407, respectively, and is included in cost of revenues in the accompanying condensed consolidated statements of income. Included in these depreciation and amortization expense totals are depreciation and amortization expense on financing lease assets of $532 and $532 for the three months ended March 31, 2020 and 2019, respectively. The Company evaluates long-lived assets for impairment as events or changes in circumstances indicate the carrying value of these assets may not be fully recoverable. Examples of such triggering events applicable to our assets include a significant decrease in the market price of a long-lived asset or asset group or a current-period operating or cash flow loss combined with a history of operating or cash flow losses or a projection or forecast that demonstrates continuing losses associated with the use of a long-lived asset or asset group.The Company performs its annual long-lived assets impairment testing in the fourth quarter of each year. In addition to the annua l impairment test, the Company regularly assesses whether a triggering event has occurred which would require interim impairment testing. The Company assessed the impact that the current macroeconomic environment surrounding the COVID-19 pandemic has or is expected to have on the business, and concluded that it was not a triggering event for impairment purposes and there was no indication of impairment of long-lived assets for the three months ended March 31, 2020. The Company capitalizes interest costs relating to construction financing during the period of construction. Capitalized interest is included in energy assets, net in the Company’s condensed consolidated balance sheets. Capitalized interest is amortized to cost of revenues in the Company’s condensed consolidated statements of income on a straight line basis over the useful life of the associated energy asset. The Company capitalized $862 and $788 of interest during the three months ended March 31, 2020 and 2019, respectively. As of March 31, 2020 and December 31, 2019, there are three ESPC asset projects which are included within energy assets, net on the Company’s condensed consolidated balance sheets. The Company controls and operates the assets as well as obtains financing during the construction period of the assets. As the Company has an obligation to the customer for performance of the asset, the Company records a liability associated with these energy assets, although, the customer is responsible for payments to the lender based on the energy asset’s production. As of March 31, 2020 and December 31, 2019, the liabilities recognized in association with these assets were $11,105 and $10,243, respectively, of which $217 and $827, respectively, has been classified as the current portion and is included in accrued expenses and other current liabilities. The remainder is included in other liabilities in the accompanying condensed consolidated balance sheets. During the three months ended March 31, 2020, the Company did not acquire any projects. The Company has a definitive agreement from prior periods to purchase ten solar projects from developers for a total purchase price of $13,902, of which, the Company has paid $366 to the developers of the projects. As of March 31, 2020, the Company has remaining deferred purchase price consideration on previously closed projects of $6,693 that will be paid upon final completion of the respective projects and throughout 2020. As of March 31, 2020, the Company had $1,431 in asset retirement obligations (“AROs”) assets recorded in project assets, net of accumulated depreciation, and $1,559 in ARO liabilities recorded in accrued expenses and other current liabilities and other liabilities. During the three months ended March 31, 2020 and 2019, the Company recorded $19 and $11, respectively, of depreciation expense related to the ARO asset. During the three months ended March 31, 2020 and 2019, the Company recorded $21 and $9, respectively, in accretion expense to the ARO liability, which is reflected in the accretion of ARO and contingent consideration on the condensed consolidated statements of cash flows. The Company’s current ARO liabilities relate to the removal of equipment and pipelines at certain renewable gas projects and obligations related to the decommissioning of certain solar facilities.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES The Company recorded a benefit for income taxes of $2,503 and provision for income tax of $257 for the three months ended March 31, 2020 and 2019, respectively. The estimated effective annualized tax rate impacted by the period discrete items is (60.6%) of benefit for the three months ended March 31, 2020, compared to a 8.2% of provision estimated effective annualized tax rate for the three months ended March 31, 2019. The principal reason for the difference between the statutory rate and the estimated annual effective rate for 2020 were the effects of investment tax credits to which the Company is entitled from solar plants which have been placed into service or are forecasted to be placed into service during 2020. Tax deductions related to Section 179D deduction, tax basis adjustments on certain partnership flip transactions and tax rate benefits associated with net operating loss carryback made possible by the passing of the COVID-19 CARES Act on March 27, 2020. The principal reason for the difference between the statutory rate and the estimated annual effective rate for 2019 were the effects of investment tax credits to which the Company is entitled from solar plants which have been placed into service or were forecasted to be placed into service during 2019. The investment tax credits and production tax credits to which the Company may be entitled fluctuate from year to year based on the cost of the renewable energy plants the Company places or expects to place in service and production levels at company owned facilities in that year. As part of the Tax Extender and Disaster Relief Act of 2019, signed into law December 20, 2019, Section 179D was extended through December 31, 2020. A reconciliation of the beginning and ending balances of the total amounts of gross unrecognized tax benefits is as follows: Gross Unrecognized Tax Benefits Balance, December 31, 2019 $ 400 Additions for prior year tax positions — Settlements with tax authorities — Reductions of prior year tax positions — Balance, March 31, 2020 $ 400 At March 31, 2020 and December 31, 2019, the Company had approximately $400 of total gross unrecognized tax benefits. At March 31, 2020 and December 31, 2019, the Company had approximately $80 and $80, respectively, of total gross unrecognized tax benefits (both net of the federal benefit on state amounts) representing the amount of unrecognized tax benefits that, if recognized, would favorably affect the effective income tax rate in any future periods. The Company has presented all deferred tax assets and liabilities as noncurrent, net assets on its condensed consolidated balance sheets as of March 31, 2020. As of December 31, 2019, the Company presented all deferred tax assets and liabilities as noncurrent net liabilities.

Leases

Leases	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Leases	LEASES On January 1, 2019, the Company adopted ASU No. 2016-02, Leases (Topic 842), using the modified retrospective approach. The Company elected the package of practical expedients available in the standard and as a result, did not reassess the lease classification of existing contracts or leases or the initial direct costs associated with existing leases. The Company has also elected the practical expedient to not separate lease components and non-lease components and will account for the leases as a single lease component for all classes of leases. As a result of the adoption of ASC 842, the Company recognized an increase in lease ROU assets of $31,639, current portions of operating lease ROU liabilities of $5,084 and an increase to long-term portions of operating lease liabilities of $28,480. There was no net impact to the condensed consolidated statements of income or retained earnings for the adoption of ASC 842. No impairment was recognized on the ROU asset upon adoption. These adjustments are detailed as follows: As of January 1, 2019 As Reported 842 Adjustment Adjusted Balances Operating Leases: Operating lease assets $ — $ 31,639 $ 31,639 Current portions of operating lease liabilities — 5,084 5,084 Long-term portions of operating lease liabilities — 28,480 28,480 Total operating lease liabilities $ — $ 33,564 $ 33,564 Weighted-average remaining lease term 10 years Weighted-average discount rate 6.0 % Financing Leases: Energy assets, net $ 38,263 $ — $ 38,263 Current portions of financing lease liabilities 4,956 — 4,956 Long-term financing lease liabilities, net of current portions and of deferred financing fees 28,407 — 28,407 Total financing lease liabilities $ 33,363 $ — $ 33,363 Weighted-average remaining lease term 18 years Weighted-average discount rate 11.7 % The Company enters into a variety of operating lease agreements through the normal course of its business including certain administrative offices. The leases are long-term, non-concealable real estate lease agreements, expiring at various dates through fiscal 2028. The agreements generally provide for fixed minimum rental payments and the payment of utilities, real estate taxes, insurance and repairs. The Company also leases certain land parcels related to our energy projects, expiring at various dates through fiscal 2045. The office and land leases make up a significant portion of the Company’s operating lease activity. Many of these leases have one or more renewal options that allow the Company, at its discretion, to renew the lease for six months to seven years. Only renewal options that the Company believed were likely to be exercised were included in our lease calculations. Many land leases include minimum lease payments that increase when the related project becomes operational. In these cases, the commercial operation date was estimated by the Company and used to calculate the estimated minimum lease payments. The Company also enters into leases for IT equipment and service agreements, automobiles, and other leases related to our construction projects such as equipment, mobile trailers and other temporary structures. The Company utilizes the portfolio approach for this class of lease. These leases are either short-term in nature or immaterial. A portion of the Company’s real estate leases are generally subject to annual changes in the Consumer Price Index (“CPI”). The Company utilized each lease’s minimum lease payments to calculate the lease balances upon transition. The subsequent increases in rent based on changes in CPI were excluded and will be excluded for future leases from the calculation of the lease balances, but will be recorded to the condensed consolidated statements of income as part of our operating lease costs. The Company has elected the practical expedient to not separate lease and non-lease components for existing leases for real estate and land leases. The Company has historical leases under ASC 840, Leases, which may have lease and non-lease components. Upon adoption of Topic 842, the Company has elected to continue to account for these historical leases as a single component, as permitted by Topic 842. As of January 1, 2019, as it relates to all prospective leases, the Company will allocate consideration to lease and non-lease components based on pricing information in the respective lease agreement, or, if this information is not available, the Company will make a good faith estimate based on the available pricing information at the time of the lease agreement. The discount rate was calculated using an incremental borrowing rate based on financing rates on secured comparable notes with comparable terms and a synthetic credit rating calculated by a third party. The Company elected to apply the discount rate using the remaining lease term at the date of adoption. The Company has a number of leases that are classified as financing leases, which relate to transactions that are considered sale-leasebacks under ASC 840. See the sale-leaseback section below for additional information on the Company’s financing leases. Supplemental balance sheet information related to leases at March 31, 2020 and December 31, 2019 is as follows: March 31, 2020 December 31, 2019 Operating Leases: Operating lease assets $ 32,444 $ 32,791 Current operating lease liabilities 5,360 5,802 Long-term portions of operating lease liabilities 29,104 29,101 Total operating lease liabilities $ 34,464 $ 34,903 Weighted-average remaining lease term 11 years 11 years Weighted-average discount rate 6.4 % 6.3 % Financing Leases: Energy assets, net $ 35,602 $ 36,134 Current portions of financing lease liabilities 4,906 4,997 Long-term financing lease liabilities, less current portions and net of deferred financing fees 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Weighted-average remaining lease term 17 years 17 years Weighted-average discount rate 11.8 % 11.8 % The costs related to our leases are as follows: Three Months Ended March 31, 2020 Three Months Ended March 31, 2019 Operating Lease: Operating lease costs $ 1,826 $ 1,838 Financing Lease: Amortization expense 532 532 Interest on lease liabilities 801 949 Total lease costs $ 3,159 $ 3,319 The Company’s estimated minimum future lease obligations under our leases are as follows: Operating Leases Financing Leases Year ended December 31, 2020 $ 5,816 $ 7,852 2021 6,506 6,792 2022 5,895 5,178 2023 4,607 3,676 2024 3,791 2,565 Thereafter 22,723 24,080 Total minimum lease payments $ 49,338 $ 50,143 Less: interest 14,874 21,765 Present value of lease liabilities $ 34,464 $ 28,378 The Company has determined that certain power purchase agreements (“PPAs”) contain a lease component in accordance with ASC 840, Leases. The Company recognized $2,245 and $2,224 of operating lease revenue under these agreements during the three months ended March 31, 2020 and 2019, respectively, which was reflected in revenues on the condensed consolidated statements of income. Sale-Leaseback For solar photovoltaic (“solar PV”) projects that the Company has determined not to be integral equipment, the Company then determines if the leaseback should be classified as a financing lease or an operating lease. All solar PV projects sold to date under the sale-leaseback program have been determined by the Company to be financing leases. For leasebacks classified as financing leases, the Company initially records a financing lease asset and financing lease obligation in its condensed consolidated balance sheets equal to the lower of the present value of the Company’s future minimum leaseback payments or the fair value of the solar PV project. For financing leasebacks, the Company defers any gain or loss, representing the excess or shortfall of cash received from the investor compared to the net book value of the asset in the Company’s condensed consolidated balance sheets at the time of the sale. The Company records the long term portion of any deferred gain or loss in other liabilities and other assets, respectively, and the current portion of any deferred gain and loss in accrued expenses and other current liabilities and prepaid expenses and other current assets, respectively, in its condensed consolidated balance sheets and amortizes the deferred amounts over the lease term in cost of revenues in its condensed consolidated statements of income. Net amortization expense in cost of revenues related to deferred gains and losses was $55 and $38 of net gains for the three months ended March 31, 2020 and 2019, respectively. During the third quarter of 2018, the Company entered into an agreement with an investor which gives us the option to sell and contemporaneously lease back solar PV projects through August 2019 up to a maximum funding amount of $100.0 million. In January 2020, the Company amended the August 2018 agreement with the investor to extend the end date of the agreement to November 24, 2020 and increase the maximum funding amount up to $150.0 million. During the three months ended March 31, 2020, the Company did not complete any acquisitions of solar PV projects and $131.0 million remained available under the lending commitment. A summary of amounts related to sale leasebacks in the Company’s condensed consolidated balance sheets is as follows: March 31, December 31, 2020 2019 Financing lease assets, net $ 35,602 $ 36,134 Deferred loss, short-term, net 115 115 Deferred loss, long-term, net 1,773 1,801 Total deferred loss $ 1,888 $ 1,916 Financing lease liabilities, short-term 4,906 4,997 Financing lease liabilities, long-term 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Deferred gain, short-term, net 345 345 Deferred gain, long-term, net 5,379 5,463 Total deferred gain $ 5,724 $ 5,808
Leases	LEASES On January 1, 2019, the Company adopted ASU No. 2016-02, Leases (Topic 842), using the modified retrospective approach. The Company elected the package of practical expedients available in the standard and as a result, did not reassess the lease classification of existing contracts or leases or the initial direct costs associated with existing leases. The Company has also elected the practical expedient to not separate lease components and non-lease components and will account for the leases as a single lease component for all classes of leases. As a result of the adoption of ASC 842, the Company recognized an increase in lease ROU assets of $31,639, current portions of operating lease ROU liabilities of $5,084 and an increase to long-term portions of operating lease liabilities of $28,480. There was no net impact to the condensed consolidated statements of income or retained earnings for the adoption of ASC 842. No impairment was recognized on the ROU asset upon adoption. These adjustments are detailed as follows: As of January 1, 2019 As Reported 842 Adjustment Adjusted Balances Operating Leases: Operating lease assets $ — $ 31,639 $ 31,639 Current portions of operating lease liabilities — 5,084 5,084 Long-term portions of operating lease liabilities — 28,480 28,480 Total operating lease liabilities $ — $ 33,564 $ 33,564 Weighted-average remaining lease term 10 years Weighted-average discount rate 6.0 % Financing Leases: Energy assets, net $ 38,263 $ — $ 38,263 Current portions of financing lease liabilities 4,956 — 4,956 Long-term financing lease liabilities, net of current portions and of deferred financing fees 28,407 — 28,407 Total financing lease liabilities $ 33,363 $ — $ 33,363 Weighted-average remaining lease term 18 years Weighted-average discount rate 11.7 % The Company enters into a variety of operating lease agreements through the normal course of its business including certain administrative offices. The leases are long-term, non-concealable real estate lease agreements, expiring at various dates through fiscal 2028. The agreements generally provide for fixed minimum rental payments and the payment of utilities, real estate taxes, insurance and repairs. The Company also leases certain land parcels related to our energy projects, expiring at various dates through fiscal 2045. The office and land leases make up a significant portion of the Company’s operating lease activity. Many of these leases have one or more renewal options that allow the Company, at its discretion, to renew the lease for six months to seven years. Only renewal options that the Company believed were likely to be exercised were included in our lease calculations. Many land leases include minimum lease payments that increase when the related project becomes operational. In these cases, the commercial operation date was estimated by the Company and used to calculate the estimated minimum lease payments. The Company also enters into leases for IT equipment and service agreements, automobiles, and other leases related to our construction projects such as equipment, mobile trailers and other temporary structures. The Company utilizes the portfolio approach for this class of lease. These leases are either short-term in nature or immaterial. A portion of the Company’s real estate leases are generally subject to annual changes in the Consumer Price Index (“CPI”). The Company utilized each lease’s minimum lease payments to calculate the lease balances upon transition. The subsequent increases in rent based on changes in CPI were excluded and will be excluded for future leases from the calculation of the lease balances, but will be recorded to the condensed consolidated statements of income as part of our operating lease costs. The Company has elected the practical expedient to not separate lease and non-lease components for existing leases for real estate and land leases. The Company has historical leases under ASC 840, Leases, which may have lease and non-lease components. Upon adoption of Topic 842, the Company has elected to continue to account for these historical leases as a single component, as permitted by Topic 842. As of January 1, 2019, as it relates to all prospective leases, the Company will allocate consideration to lease and non-lease components based on pricing information in the respective lease agreement, or, if this information is not available, the Company will make a good faith estimate based on the available pricing information at the time of the lease agreement. The discount rate was calculated using an incremental borrowing rate based on financing rates on secured comparable notes with comparable terms and a synthetic credit rating calculated by a third party. The Company elected to apply the discount rate using the remaining lease term at the date of adoption. The Company has a number of leases that are classified as financing leases, which relate to transactions that are considered sale-leasebacks under ASC 840. See the sale-leaseback section below for additional information on the Company’s financing leases. Supplemental balance sheet information related to leases at March 31, 2020 and December 31, 2019 is as follows: March 31, 2020 December 31, 2019 Operating Leases: Operating lease assets $ 32,444 $ 32,791 Current operating lease liabilities 5,360 5,802 Long-term portions of operating lease liabilities 29,104 29,101 Total operating lease liabilities $ 34,464 $ 34,903 Weighted-average remaining lease term 11 years 11 years Weighted-average discount rate 6.4 % 6.3 % Financing Leases: Energy assets, net $ 35,602 $ 36,134 Current portions of financing lease liabilities 4,906 4,997 Long-term financing lease liabilities, less current portions and net of deferred financing fees 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Weighted-average remaining lease term 17 years 17 years Weighted-average discount rate 11.8 % 11.8 % The costs related to our leases are as follows: Three Months Ended March 31, 2020 Three Months Ended March 31, 2019 Operating Lease: Operating lease costs $ 1,826 $ 1,838 Financing Lease: Amortization expense 532 532 Interest on lease liabilities 801 949 Total lease costs $ 3,159 $ 3,319 The Company’s estimated minimum future lease obligations under our leases are as follows: Operating Leases Financing Leases Year ended December 31, 2020 $ 5,816 $ 7,852 2021 6,506 6,792 2022 5,895 5,178 2023 4,607 3,676 2024 3,791 2,565 Thereafter 22,723 24,080 Total minimum lease payments $ 49,338 $ 50,143 Less: interest 14,874 21,765 Present value of lease liabilities $ 34,464 $ 28,378 The Company has determined that certain power purchase agreements (“PPAs”) contain a lease component in accordance with ASC 840, Leases. The Company recognized $2,245 and $2,224 of operating lease revenue under these agreements during the three months ended March 31, 2020 and 2019, respectively, which was reflected in revenues on the condensed consolidated statements of income. Sale-Leaseback For solar photovoltaic (“solar PV”) projects that the Company has determined not to be integral equipment, the Company then determines if the leaseback should be classified as a financing lease or an operating lease. All solar PV projects sold to date under the sale-leaseback program have been determined by the Company to be financing leases. For leasebacks classified as financing leases, the Company initially records a financing lease asset and financing lease obligation in its condensed consolidated balance sheets equal to the lower of the present value of the Company’s future minimum leaseback payments or the fair value of the solar PV project. For financing leasebacks, the Company defers any gain or loss, representing the excess or shortfall of cash received from the investor compared to the net book value of the asset in the Company’s condensed consolidated balance sheets at the time of the sale. The Company records the long term portion of any deferred gain or loss in other liabilities and other assets, respectively, and the current portion of any deferred gain and loss in accrued expenses and other current liabilities and prepaid expenses and other current assets, respectively, in its condensed consolidated balance sheets and amortizes the deferred amounts over the lease term in cost of revenues in its condensed consolidated statements of income. Net amortization expense in cost of revenues related to deferred gains and losses was $55 and $38 of net gains for the three months ended March 31, 2020 and 2019, respectively. During the third quarter of 2018, the Company entered into an agreement with an investor which gives us the option to sell and contemporaneously lease back solar PV projects through August 2019 up to a maximum funding amount of $100.0 million. In January 2020, the Company amended the August 2018 agreement with the investor to extend the end date of the agreement to November 24, 2020 and increase the maximum funding amount up to $150.0 million. During the three months ended March 31, 2020, the Company did not complete any acquisitions of solar PV projects and $131.0 million remained available under the lending commitment. A summary of amounts related to sale leasebacks in the Company’s condensed consolidated balance sheets is as follows: March 31, December 31, 2020 2019 Financing lease assets, net $ 35,602 $ 36,134 Deferred loss, short-term, net 115 115 Deferred loss, long-term, net 1,773 1,801 Total deferred loss $ 1,888 $ 1,916 Financing lease liabilities, short-term 4,906 4,997 Financing lease liabilities, long-term 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Deferred gain, short-term, net 345 345 Deferred gain, long-term, net 5,379 5,463 Total deferred gain $ 5,724 $ 5,808
Leases	LEASES On January 1, 2019, the Company adopted ASU No. 2016-02, Leases (Topic 842), using the modified retrospective approach. The Company elected the package of practical expedients available in the standard and as a result, did not reassess the lease classification of existing contracts or leases or the initial direct costs associated with existing leases. The Company has also elected the practical expedient to not separate lease components and non-lease components and will account for the leases as a single lease component for all classes of leases. As a result of the adoption of ASC 842, the Company recognized an increase in lease ROU assets of $31,639, current portions of operating lease ROU liabilities of $5,084 and an increase to long-term portions of operating lease liabilities of $28,480. There was no net impact to the condensed consolidated statements of income or retained earnings for the adoption of ASC 842. No impairment was recognized on the ROU asset upon adoption. These adjustments are detailed as follows: As of January 1, 2019 As Reported 842 Adjustment Adjusted Balances Operating Leases: Operating lease assets $ — $ 31,639 $ 31,639 Current portions of operating lease liabilities — 5,084 5,084 Long-term portions of operating lease liabilities — 28,480 28,480 Total operating lease liabilities $ — $ 33,564 $ 33,564 Weighted-average remaining lease term 10 years Weighted-average discount rate 6.0 % Financing Leases: Energy assets, net $ 38,263 $ — $ 38,263 Current portions of financing lease liabilities 4,956 — 4,956 Long-term financing lease liabilities, net of current portions and of deferred financing fees 28,407 — 28,407 Total financing lease liabilities $ 33,363 $ — $ 33,363 Weighted-average remaining lease term 18 years Weighted-average discount rate 11.7 % The Company enters into a variety of operating lease agreements through the normal course of its business including certain administrative offices. The leases are long-term, non-concealable real estate lease agreements, expiring at various dates through fiscal 2028. The agreements generally provide for fixed minimum rental payments and the payment of utilities, real estate taxes, insurance and repairs. The Company also leases certain land parcels related to our energy projects, expiring at various dates through fiscal 2045. The office and land leases make up a significant portion of the Company’s operating lease activity. Many of these leases have one or more renewal options that allow the Company, at its discretion, to renew the lease for six months to seven years. Only renewal options that the Company believed were likely to be exercised were included in our lease calculations. Many land leases include minimum lease payments that increase when the related project becomes operational. In these cases, the commercial operation date was estimated by the Company and used to calculate the estimated minimum lease payments. The Company also enters into leases for IT equipment and service agreements, automobiles, and other leases related to our construction projects such as equipment, mobile trailers and other temporary structures. The Company utilizes the portfolio approach for this class of lease. These leases are either short-term in nature or immaterial. A portion of the Company’s real estate leases are generally subject to annual changes in the Consumer Price Index (“CPI”). The Company utilized each lease’s minimum lease payments to calculate the lease balances upon transition. The subsequent increases in rent based on changes in CPI were excluded and will be excluded for future leases from the calculation of the lease balances, but will be recorded to the condensed consolidated statements of income as part of our operating lease costs. The Company has elected the practical expedient to not separate lease and non-lease components for existing leases for real estate and land leases. The Company has historical leases under ASC 840, Leases, which may have lease and non-lease components. Upon adoption of Topic 842, the Company has elected to continue to account for these historical leases as a single component, as permitted by Topic 842. As of January 1, 2019, as it relates to all prospective leases, the Company will allocate consideration to lease and non-lease components based on pricing information in the respective lease agreement, or, if this information is not available, the Company will make a good faith estimate based on the available pricing information at the time of the lease agreement. The discount rate was calculated using an incremental borrowing rate based on financing rates on secured comparable notes with comparable terms and a synthetic credit rating calculated by a third party. The Company elected to apply the discount rate using the remaining lease term at the date of adoption. The Company has a number of leases that are classified as financing leases, which relate to transactions that are considered sale-leasebacks under ASC 840. See the sale-leaseback section below for additional information on the Company’s financing leases. Supplemental balance sheet information related to leases at March 31, 2020 and December 31, 2019 is as follows: March 31, 2020 December 31, 2019 Operating Leases: Operating lease assets $ 32,444 $ 32,791 Current operating lease liabilities 5,360 5,802 Long-term portions of operating lease liabilities 29,104 29,101 Total operating lease liabilities $ 34,464 $ 34,903 Weighted-average remaining lease term 11 years 11 years Weighted-average discount rate 6.4 % 6.3 % Financing Leases: Energy assets, net $ 35,602 $ 36,134 Current portions of financing lease liabilities 4,906 4,997 Long-term financing lease liabilities, less current portions and net of deferred financing fees 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Weighted-average remaining lease term 17 years 17 years Weighted-average discount rate 11.8 % 11.8 % The costs related to our leases are as follows: Three Months Ended March 31, 2020 Three Months Ended March 31, 2019 Operating Lease: Operating lease costs $ 1,826 $ 1,838 Financing Lease: Amortization expense 532 532 Interest on lease liabilities 801 949 Total lease costs $ 3,159 $ 3,319 The Company’s estimated minimum future lease obligations under our leases are as follows: Operating Leases Financing Leases Year ended December 31, 2020 $ 5,816 $ 7,852 2021 6,506 6,792 2022 5,895 5,178 2023 4,607 3,676 2024 3,791 2,565 Thereafter 22,723 24,080 Total minimum lease payments $ 49,338 $ 50,143 Less: interest 14,874 21,765 Present value of lease liabilities $ 34,464 $ 28,378 The Company has determined that certain power purchase agreements (“PPAs”) contain a lease component in accordance with ASC 840, Leases. The Company recognized $2,245 and $2,224 of operating lease revenue under these agreements during the three months ended March 31, 2020 and 2019, respectively, which was reflected in revenues on the condensed consolidated statements of income. Sale-Leaseback For solar photovoltaic (“solar PV”) projects that the Company has determined not to be integral equipment, the Company then determines if the leaseback should be classified as a financing lease or an operating lease. All solar PV projects sold to date under the sale-leaseback program have been determined by the Company to be financing leases. For leasebacks classified as financing leases, the Company initially records a financing lease asset and financing lease obligation in its condensed consolidated balance sheets equal to the lower of the present value of the Company’s future minimum leaseback payments or the fair value of the solar PV project. For financing leasebacks, the Company defers any gain or loss, representing the excess or shortfall of cash received from the investor compared to the net book value of the asset in the Company’s condensed consolidated balance sheets at the time of the sale. The Company records the long term portion of any deferred gain or loss in other liabilities and other assets, respectively, and the current portion of any deferred gain and loss in accrued expenses and other current liabilities and prepaid expenses and other current assets, respectively, in its condensed consolidated balance sheets and amortizes the deferred amounts over the lease term in cost of revenues in its condensed consolidated statements of income. Net amortization expense in cost of revenues related to deferred gains and losses was $55 and $38 of net gains for the three months ended March 31, 2020 and 2019, respectively. During the third quarter of 2018, the Company entered into an agreement with an investor which gives us the option to sell and contemporaneously lease back solar PV projects through August 2019 up to a maximum funding amount of $100.0 million. In January 2020, the Company amended the August 2018 agreement with the investor to extend the end date of the agreement to November 24, 2020 and increase the maximum funding amount up to $150.0 million. During the three months ended March 31, 2020, the Company did not complete any acquisitions of solar PV projects and $131.0 million remained available under the lending commitment. A summary of amounts related to sale leasebacks in the Company’s condensed consolidated balance sheets is as follows: March 31, December 31, 2020 2019 Financing lease assets, net $ 35,602 $ 36,134 Deferred loss, short-term, net 115 115 Deferred loss, long-term, net 1,773 1,801 Total deferred loss $ 1,888 $ 1,916 Financing lease liabilities, short-term 4,906 4,997 Financing lease liabilities, long-term 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Deferred gain, short-term, net 345 345 Deferred gain, long-term, net 5,379 5,463 Total deferred gain $ 5,724 $ 5,808

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES The Company from time to time issues letters of credit and performance bonds, with their third-party lenders, to provide collateral. The Company has future lease commitments which do not yet meet the criteria of a ROU asset or ROU liability as of March 31, 2020, for certain business offices. These commitments total $721 as of March 31, 2020 and relate to payments through 2026. Legal Proceedings The Company is involved in a variety of claims and other legal proceedings generally incidental to its normal business activities. While the outcome of any of these proceedings cannot be accurately predicted, the Company does not believe the ultimate resolution of any of these existing matters would have a material adverse effect on its financial condition or results of operations. Commitments as a Result of Acquisitions In August 2018, the Company completed an acquisition which provided for a revenue earn-out contingent upon the acquired business meeting certain cumulative revenue targets over five years from the acquisition date. The Company evaluated financial forecasts of the acquired business and concluded that the fair value of this earn-out was approximately $555, which was subsequently increased to $678 as of December 31, 2019 which remained consistent at March 31, 2020, and is recorded in the other liabilities on the condensed consolidated balance sheets. The contingent consideration will be paid annually, commencing in 2020, if any of the cumulative revenue targets are achieved. The fair value of the earn-out will be re-evaluated at each reporting period and adjustments will be recorded as needed. See Note 10 for additional information.

Fair Value Measurement

Fair Value Measurement	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurement	FAIR VALUE MEASUREMENT The Company recognizes certain financial assets and liabilities at fair value on a recurring basis (at least annually). Fair value is defined as the price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Three levels of inputs that may be used to measure fair value are as follows: Level 1: Inputs are based upon unadjusted quoted prices for identical instruments traded in active markets. Level 2: Inputs are based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3: Inputs are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The fair values are therefore determined using model-based techniques that include option pricing models, discounted cash flow models, and similar techniques. The following table presents the input level used to determine the fair values of the Company’s financial instruments measured at fair value on a recurring basis: Fair Value as of March 31, December 31, Level 2020 2019 Assets: Interest rate swap instruments 2 $ — $ 15 Commodity swap instruments 2 246 198 Total assets $ 246 $ 213 Liabilities: Interest rate swap instruments 2 $ 10,882 $ 6,236 Interest make-whole provisions 2 733 918 Contingent consideration 3 678 678 Total liabilities $ 12,293 $ 7,832 The fair value of the Company’s interest rate swaps was determined using cash flow analysis on the expected cash flow of the contract in combination with observable market-based inputs, including interest rate curves and implied volatilities. As part of this valuation, the Company considered the credit ratings of the counterparties to the interest rate swaps to determine if a credit risk adjustment was required. The fair value of the Company’s commodity swaps was determined using a cash flow analysis on the expected cash flow of the contract in combination with observable forward price inputs obtained from a third-party pricing source. As part of this valuation, the Company considered the credit ratings of the counterparties to the commodity swaps to determine if a credit risk adjustment was required. The fair value of the Company’s make-whole provisions were determined by comparing them against the rates of similar debt instruments under similar terms without a make-whole provision obtained from various highly rated third-party pricing sources. The fair value of the Company’s contingent consideration liabilities were determined by evaluating the acquired asset’s future financial forecasts and evaluating which, if any, of the cumulative revenue targets, financial metrics and/or milestones are likely to be met. The Company has classified contingent consideration related to certain acquisitions within level 3 of the fair value hierarchy because the fair value is derived using significant unobservable inputs, which include discount rates and probability-weighted cash flows. The Company determined the fair value of its contingent consideration obligations based on a probability-weighted income approach derived from financial performance estimates and probability assessments of the attainment of certain targets. The Company establishes discount rates to be utilized in its valuation models based on the cost to borrow that would be required by a market participant for similar instruments. The key assumptions as of March 31, 2020, related to the contingent consideration from the acquisition of certain assets of Chelsea Group Limited, used in the model include a discount rate of 18% for purposes of discounting the low and base case scenarios associated with achievement of the financial based earn-out. The probabilities assigned to these scenarios were 50% for both the low and base case scenarios. An increase or decrease in the probability of achievement of any scenario could result in a significant increase or decrease to the estimated fair value of the contingent consideration liability. The following table sets forth a summary of changes in fair value of contingent liabilities classified as Level 3 for the three months ended March 31, 2020 and March 31, 2019: Three Months Ended Three Months Ended March 31, 2020 March 31, 2019 Contingent consideration liabilities balance at December 31, 2019 and 2018 $ 678 $ 600 Changes in the fair value of contingent consideration obligation — 25 Contingent consideration liabilities balance at March 31, 2020 and 2019 $ 678 $ 625 The fair value of financial instruments is determined by reference to observable market data and other valuation techniques, as appropriate. The only category of financial instruments where the difference between fair value and recorded book value is notable is long-term debt. At March 31, 2020 and December 31, 2019 the fair value of the Company’s long-term debt was estimated using discounted cash flows analysis, based on the Company’s current incremental borrowing rates for similar types of borrowing arrangements which are considered to be level two inputs. There have been no transfers in or out of level two or level three financial instruments for the three months ended March 31, 2020 and the year ended December 31, 2019. Based on the analysis performed, the fair value and the carrying value of the Company’s long-term debt, excluding financing leases, are as follows: As of March 31, 2020 As of December 31, 2019 Fair Value Carrying Value Fair Value Carrying Value Long-term debt (Level 2) $ 332,683 $ 326,459 $ 309,377 $ 307,508 The Company is also required periodically to measure certain other assets at fair value on a nonrecurring basis, including long-lived assets, goodwill and other intangible assets. There were no assets recorded at fair value on a non-recurring basis at March 31, 2020 or December 31, 2019.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES At March 31, 2020 and December 31, 2019, the following table presents information about the fair value amounts of the Company’s derivative instruments are as follows: Derivatives as of March 31, 2020 December 31, 2019 Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives Designated as Hedging Instruments: Interest rate swap contracts Other assets $ — Other assets $ 15 Interest rate swap contracts Other liabilities 10,846 Other liabilities 6,210 Derivatives Not Designated as Hedging Instruments: Interest rate swap contracts Other liabilities $ 36 Other liabilities $ 26 Commodity swap contracts Other assets 246 Other assets 198 Commodity swap contracts Other liabilities — Other liabilities — Interest make-whole provisions Other liabilities 733 Other liabilities 918 As of March 31, 2020 and December 31, 2019 all but three of the Company’s freestanding derivatives were designated as hedging instruments. The following tables present information about the effects of the Company’s derivative instruments on the condensed consolidated statements of income and condensed consolidated statements of comprehensive income: Location of (Gain) Loss Recognized in Net Income Amount of (Gain) Loss Recognized in Net Income Three Months Ended March 31, 2020 2019 Derivatives Designated as Hedging Instruments: Interest rate swap contracts Other expenses, net $ 99 $ (49) Derivatives Not Designated as Hedging Instruments: Interest rate swap contracts Other expenses, net $ 10 $ — Commodity swap contracts Other expenses, net (48) — Interest make-whole provision Other expenses, net (185) (723) Three Months Ended March 31, 2020 Derivatives Designated as Hedging Instruments: Accumulated loss in AOCI at the beginning of the period $ (4,742) Unrealized loss recognized in AOCI (3,564) Loss reclassified from AOCI to other expenses, net 99 Accumulated loss in AOCI at the end of the period $ (8,207) The following tables present a listing of all the Company’s active derivative instruments as of March 31, 2020: Active Interest Rate Swap Effective Date Expiration Date Initial Notional Amount ($) Status 11-Year, 5.77% Fixed October 2018 October 2029 $ 9,200 Designated 15-Year, 5.24% Fixed June 2018 June 2033 10,000 Designated 3-Year, 2.46% Fixed March 2018 December 2020 17,100 Not Designated 10-Year, 4.74% Fixed June 2017 December 2027 14,100 Designated 15-Year, 3.26% Fixed February 2023 December 2038 14,084 Designated 7-Year, 2.19% Fixed February 2016 February 2023 20,746 Designated 8-Year, 3.70% Fixed March 2020 June 2028 14,643 Designated 8-Year, 3.70% Fixed March 2020 June 2028 10,734 Designated 15-Year, 5.30% Fixed February 2006 February 2021 3,256 Designated 15.5-Year, 5.40% Fixed September 2008 March 2024 13,081 Designated Active Commodity Swap Effective Date Expiration Date Initial Notional Amount (Volume) Commodity Measurement Status 1-Year, $2.68 MMBtu Fixed May 2019 April 2020 437,004 MMBtus Not Designated 1-Year, $2.70 MMBtu Fixed May 2020 April 2021 435,810 MMBtus Not Designated Other Derivatives Classification Effective Date Expiration Date Fair Value ($) Interest make-whole provisions Liability June/August 2018 December 2038 $ 733

Investment Funds and Other Vari

Investment Funds and Other Variable Interest Entities	3 Months Ended
	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Investment Funds and Other Variable Interest Entities	INVESTMENT FUNDS AND OTHER VARIABLE INTEREST ENTITIES Investment Funds In each of September 2015, June 2017, June 2018, October 2018, and December 2019, the Company formed an investment fund with a different third-party investor which granted the applicable investor ownership interests in the net assets of certain of the Company’s renewable energy project subsidiaries. The Company currently has five such investment funds each with a different third-party investor. The Company consolidates the investment funds, and all inter-company balances and transactions between the Company and the investment funds are eliminated in its condensed consolidated financial statements. The Company determined that the investment funds meet the definition of a variable interest entity (“VIE”). The Company uses a qualitative approach in assessing the consolidation requirement for VIEs that focuses on determining whether the Company has the power to direct the activities of the VIE that most significantly affect the VIE’s economic performance and whether the Company has the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. The Company has considered the provisions within the contractual arrangements that grant it power to manage and make decisions that affect the operation of these VIEs, including determining the solar energy systems and associated long term customer contracts to be sold or contributed to the VIEs, and installation, operation and maintenance of the solar energy systems. The Company considers that the rights granted to the other investors under the contractual arrangements are more protective in nature rather than participating rights. As such, the Company has determined it is the primary beneficiary of the VIEs for all periods presented. The Company evaluates its relationships with VIEs on an ongoing basis to ensure that it continues to be the primary beneficiary. Under the related agreements, cash distributions of income and other receipts by the funds, net of agreed-upon expenses and estimated expenses, tax benefits and detriments of income and loss, and tax benefits of tax credits, are assigned to the funds’ investor and Company’s subsidiaries as specified in contractual arrangements. Certain of these arrangements have call and put options to acquire the investor’s equity interest as specified in the contractual agreements. See Note 13 for additional information on the call and put options. A summary of amounts related to the investment funds in the Company’s condensed consolidated balance sheets is as follows: March 31, December 31, 2020 (1) 2019 (1) Cash and cash equivalents $ 5,789 $ 4,666 Restricted cash 586 586 Accounts receivable, net 462 532 Costs and estimated earnings in excess of billings 1,355 1,125 Prepaid expenses and other current assets 80 108 Total VIE current assets 8,272 7,017 Property and equipment, net 1,266 1,266 Energy assets, net 145,410 142,456 Operating lease assets 6,411 6,511 Other assets 1,660 1,662 Total VIE assets $ 163,019 $ 158,912 Current portions of long-term debt and financing lease liabilities $ 2,234 $ 2,252 Accounts payable 2,670 2,006 Accrued expenses and other current liabilities 1,623 2,203 Current portions of operating lease liabilities 106 102 Total VIE current liabilities 6,633 6,563 Long-term debt and financing lease liabilities, less current portions and net of deferred financing fees 24,214 24,654 Long-term portions of operating lease liabilities 6,173 6,180 Other liabilities 1,004 1,171 Total VIE liabilities $ 38,024 $ 38,568 (1) The amounts in the above table are reflected in Note 1 on the Company’s condensed consolidated balance sheets. See the Company’s condensed consolidated balance sheets for additional information. Other Variable Interest Entities The Company follows guidance on the consolidation of VIEs that requires companies to utilize a qualitative approach to determine whether it is the primary beneficiary of a VIE. The process for identifying the primary beneficiary of a VIE requires consideration of the factors that indicate a party has the power to direct the activities that most significantly impact the joint ventures economic performance, including powers granted to the joint ventures program manager, powers contained in the joint venture governing board and, to a certain extent, a company's economic interest in the joint venture. The Company analyzes its joint ventures and classifies them as either: • a VIE that must be consolidated because the Company is the primary beneficiary or the joint venture is not a VIE and the Company holds the majority voting interest with no significant participative rights available to the other partners; or • a VIE that does not require consolidation and is treated as an equity method investment because the Company is not the primary beneficiary or the joint venture is not a VIE and the Company does not hold the majority voting interest. Many of the joint ventures are deemed to be VIEs because they lack sufficient equity to finance the activities of the joint venture.

Non-controlling Interests and E

Non-controlling Interests and Equity	3 Months Ended
	Mar. 31, 2020
Noncontrolling Interest [Abstract]
Non-controlling Interests and Equity	NON-CONTROLLING INTERESTS AND EQUITY Redeemable Non-controlling Interests The Company’s wholly owned subsidiary with a membership interest in the investment fund formed in the third quarter of 2015 has the right, beginning on the fifth anniversary of the final funding of the variable rate construction and term loans due 2023 and extending for six months, to elect to require the non-controlling interest holder to sell all of its membership units to the Company’s wholly owned subsidiary, a call option. The Company’s investment fund, which was formed in the third quarter of 2015, also includes a right, beginning on the sixth anniversary of the final funding and extending for one year, for the non-controlling interest holder to elect to require the Company’s wholly owned subsidiary to purchase all of its membership interests in the fund, a put option. The Company’s wholly owned subsidiary with a membership interest in the investment fund formed in the second quarter of 2017 has the right, beginning on the fifth anniversary of the final funding of the non-controlling interest holder and extending for six months, to elect to require the non-controlling interest holder to sell all of its membership units to the Company’s wholly owned subsidiary, a call option. The Company’s investment fund formed in the second quarter of 2017 also includes a right, beginning on the sixth anniversary of the final funding and extending for one year, for the non-controlling interest holder to elect to require the Company’s wholly owned subsidiary to purchase all of its membership interests in the fund, a put option. The Company’s wholly owned subsidiary with a membership interest in the investment fund formed in the second quarter of 2018 has the right, beginning on the fifth anniversary of the investment fund’s final project being placed into service and extending for six months, to elect to require the non-controlling interest holder to sell all of its membership units to the Company’s wholly owned subsidiary, a call option. The Company’s investment fund formed in the second quarter of 2018 also includes a right, upon the expiration of the call option and extending for six months, for the non-controlling interest holder to elect to require the Company’s wholly owned subsidiary to purchase all of its membership interests in the fund, a put option. The Company’s wholly owned subsidiary with a membership interest in the investment fund formed in the fourth quarter of 2018 has the right, beginning on the fifth anniversary on the last projects placed in-service date and extending for six months, to elect to require the non-controlling interest holder to sell all of its membership units to the Company’s wholly owned subsidiary, a call option. The Company’s investment fund formed in the fourth quarter of 2018 also includes a right, upon the expiration of the call option and extending for six months, for the non-controlling interest partner to elect to require the Company’s wholly owned subsidiary to purchase all of its membership interests in the fund, a put option. The Company’s wholly owned subsidiary with a membership interest in the investment fund formed in the fourth quarter of 2019 has the right, beginning on the fifth anniversary on the last projects placed in-service date and extending for six months, to elect to require the non-controlling interest holder to sell all of its membership units to the Company’s wholly owned subsidiary, a call option. The Company’s investment fund formed in the fourth quarter of 2019 also includes a right, beginning six months after the fifth anniversary of the final funding and extending for one year, for the non-controlling interest partner to elect to require the Company’s wholly owned subsidiary to purchase all of its membership interests in the fund, a put option. The purchase price for two of the investment funds investors’ interests under the call options is equal to the fair market value of such interest at the time the option is exercised. The purchase price for two of the investment funds investor’s interests under the call options is equal to the greater of (i) the fair market value of such interests at the time the option is exercised or (ii) 7% of the investors’ contributed capital balance at the time the option is exercisable. The purchase price for the remaining investment fund investor’s interests under the call options is equal to the greater of (i) the fair market value of such interests at the time the option is exercised or (ii) 5% of the investors’ contributed capital balance at the time the option is exercisable.The call options are exercisable beginning on the date that specified conditions are met for each respective fund. None of the call options are expected to become exercisable prior to 2021. The purchase price for two of the funds investors’ interests in the investment funds under the put options is the lessor of fair market value at the time the option is exercised and a specified amount, ranging from $659 - $917. The purchase price for the two remaining funds investors’ interest in the investment funds under the put options is the sum of (i) the fair market value at the time the option is exercised, and (ii) the closing costs incurred by the investor in connection with the exercise of the put option. The purchase price for the remaining fund investors’ interest in the investment funds under the put options is the lessor of fair market value at the time the option is exercised and the sum of (i) 5% of the investors’ contributed capital balance at the time the option is exercisable, and (ii) the fair market value of any unpaid tax law change losses incurred by the investor in connection with the exercise of the put option. The put options for the investment funds are exercisable beginning on the date that specified conditions are met for each respective fund. The put options are not expected to become exercisable prior to 2022.

Earnings Per Share and Other Eq

Earnings Per Share and Other Equity Related Information	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Share And Other Equity Related Information	EARNINGS PER SHARE AND OTHER EQUITY RELATED INFORMATION Earnings Per Share Basic earnings per share is calculated using the Company’s weighted-average outstanding common shares, including vested restricted shares. When the effects are not anti-dilutive, diluted earnings per share is calculated using the weighted-average outstanding common shares; the dilutive effect of convertible preferred stock, under the “if converted” method; and the treasury stock method with regard to warrants and stock options; all as determined under the treasury stock method. Three Months Ended March 31, 2020 2019 Net income attributable to common shareholders $ 6,201 $ 4,147 Basic weighted-average shares outstanding 47,384 46,293 Effect of dilutive securities: Stock options 1,113 1,361 Diluted weighted-average shares outstanding 48,497 47,654 For the three months ended March 31, 2020 and 2019, the total number of shares of common stock related to stock options excluded from the calculation of dilutive shares, as the effect would be anti-dilutive, were 431 and 293, respectively. Stock-Based Compensation Expense For the three months ended March 31, 2020 and 2019, the Company recorded stock-based compensation expense, including expense related to the Employee Stock Purchase Plan (“ESPP”), of $429 and $385, respectively, in connection with the stock-based payment awards. The compensation expense is included in selling, general and administrative expenses in the accompanying condensed consolidated statements of income. As of March 31, 2020, there was $10,757 of unrecognized compensation expense related to non-vested stock option awards that is expected to be recognized over a weighted-average period of 3.0 years. No awards to individuals who were not either an employee or director of the Company occurred during the three months ended March 31, 2020 or during the year ended December 31, 2019. Stock Option Grants During the three months ended March 31, 2020, the Company granted 196 common stock options to certain employees and directors under its 2010 Stock Incentive Plan, which have a contractual life of ten years and vest over a five Share Repurchase Program

Business Segment Information

Business Segment Information	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Business Segment Information	BUSINESS SEGMENT INFORMATION The Company reports results under ASC 280, Segment Reporting. The Company’s reportable segments are U.S. Regions, U.S. Federal, Canada and Non-Solar Distributed Generation (“DG”). The Company’s U.S. Regions, U.S. Federal and Canada segments offer energy efficiency products and services, which include the design, engineering and installation of equipment and other measures to improve the efficiency and control the operation of a facility’s energy infrastructure, renewable energy solutions and services, which include the construction of small-scale plants that the company owns or develops for customers that produce electricity, gas, heat or cooling from renewable sources of energy and O&M services. The Company’s Non-Solar DG segment sells electricity, processed renewable gas fuel, heat or cooling, produced from renewable sources of energy, other than solar, and generated by small-scale plants that the Company owns and O&M services for customer owned small-scale plants. The “All Other” category offers enterprise energy management services, consulting services and the sale of solar-PV energy products and systems which we refer to as integrated-PV. These segments do not include results of other activities, such as corporate operating expenses not specifically allocated to the segments. Certain reportable segments are an aggregation of operating segments. The reports of the Company’s chief operating decision maker do not include assets at the operating segment level. The accounting policies are the same as those described in the summary of significant accounting policies in Note 2 included in the Company’s annual report on Form 10-K for the year ended December 31, 2019 filed with the Securities and Exchange Commission on March 4, 2020. An analysis of the Company’s business segment information and reconciliation to the condensed consolidated financial statements is as follows: U.S. Regions U.S. Federal Canada Non-Solar DG All Other Total Consolidated Three Months Ended March 31, 2020 Revenues $ 84,727 $ 68,745 $ 11,392 $ 22,724 $ 24,825 $ 212,413 Interest income 36 40 — 14 — 90 Interest expense 1,481 746 172 1,045 15 3,459 Depreciation and amortization of intangible assets 2,763 1,017 391 5,287 376 9,834 Unallocated corporate activity — — — — — (10,346) Income before taxes, excluding unallocated corporate activity 3,723 7,094 (221) 1,669 2,212 14,477 Three Months Ended March 31, 2019 Revenues $ 55,597 $ 43,057 $ 7,148 $ 21,230 $ 23,080 $ 150,112 Interest income 63 49 — 21 — 133 Interest expense 857 210 164 1,577 — 2,808 Depreciation and amortization of intangible assets 2,182 817 275 5,216 348 8,838 Unallocated corporate activity — — — — — (8,008) Income before taxes, excluding unallocated corporate activity (278) 5,621 (289) 1,381 4,701 11,136

Debt

Debt	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Debt	DEBT As of March 31, 2020 and December 31, 2019, the Company’s debt comprised the following: Commencement Date Maturity Date Acceleration Clause (2) Rate as of March 31, 2020 March 31, 2020 December 31, 2019 Senior secured credit facility, interest at varying rates monthly in arrears June 2015 June 2024 NA 4.36 % $ 142,022 $ 112,216 Variable rate term loan payable in semi-annual installments January 2006 February 2021 Yes 3.70 % 625 625 Variable rate term loan payable in semi-annual installments January 2006 June 2024 Yes 3.45 % 6,609 6,609 Term loan payable in quarterly installments March 2011 March 2021 Yes 7.25 % 666 831 Term loan payable in monthly installments October 2011 June 2028 NA 6.11 % 3,314 3,649 Variable rate term loan payable in quarterly installments October 2012 May 2020 NA 4.95 % 27,617 28,217 Variable rate term loan payable in quarterly installments September 2015 March 2023 NA 4.20 % 15,995 15,976 Term loan payable in quarterly installments August 2016 July 2031 NA 4.95 % 3,392 3,769 Term loan payable in quarterly installments March 2017 March 2028 NA 5.00 % 3,416 3,521 Term loan payable in monthly installments April 2017 April 2027 NA 4.50 % 21,823 22,553 Term loan payable in quarterly installments April 2017 February 2034 NA 5.61 % 2,487 2,706 Variable rate term loan payable in quarterly installments June 2017 December 2027 NA 3.90 % 11,740 11,740 Variable rate term loan payable in quarterly installments February 2018 August 2022 Yes 8.95 % 12,436 15,645 Term loan payable in quarterly installments June 2018 December 2038 Yes 5.15 % 28,073 28,583 Variable rate term loan payable in semi-annual installments June 2018 June 2033 Yes 3.50 % 9,003 9,003 Variable rate term loan payable in monthly/quarterly installments October 2018 October 2029 Yes 3.94 % 8,923 9,092 Long term finance liability in semi-annual installments (3) July 2019 July 2039 NA 0.28 % 3,785 3,841 Long term finance liability in semi-annual installments (3) November 2019 November 2039 NA — % 6,970 8,794 Term loan payable in quarterly installments December 2019 December 2021 Yes 6.500 % 24,167 27,226 Financing leases (1) 28,378 28,497 $ 361,441 $ 343,093 Less - current maturities 69,282 69,969 Less - deferred financing fees 6,606 6,943 Long term debt and financing lease liabilities $ 285,553 $ 266,181 (1) Financing leases do not include approximately $21,765 in future interest payments (2) These agreements have acceleration causes that, in the event of default, as defined, the payee has the option to accelerate payment terms and make due the remaining principal and the required interest balance according to the agreement (3) These agreements are sale-leaseback arrangements that provides for the sale of solar PV projects to a third party investor and the simultaneous leaseback of the projects. In accordance with Topic 842, Leases, these transactions are accounted for as a failed sale as the Company retains control of the underlying assets and as such, are classified as financing liabilities. The low interest rates are the results of tax credits which were transferred to the counterparty. Senior Secured Credit Facility - Revolver and Term Loan As of March 31, 2020, the Company amended the Company’s senior secured credit facility which increased the total funded debt to EBITDA covenant ratio to a maximum of 3.75 from 3.25 for the year ended December 31, 2020. The amendment also increased the Eurocurrency Rate floor to 1% from 0%. The total commitment under the amended credit facility (revolving credit, term loan and swing line) remains unchanged, which is $185,000 . At March 31, 2020, funds of $20,736 are available for borrowing under the revolving credit facility. Variable Rate Term Loan

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Fair Value Measurement In August 2018, the FASB issued ASU 2018-13 Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement, which modifies the disclosure requirements on fair value measurements. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company adopted this guidance as of January 1, 2020 and the adoption did not have a material impact on the Company’s consolidated financial statements. Consolidations In October 2018, the FASB issued ASU No. 2018-17, Consolidation (Topic 810), Targeted Improvements to Related Party Guidance for Variable Interest Entities, which aligns the evaluation of whether a decision maker's fee is a variable interest with the guidance in the primary beneficiary test by requiring the decision maker to consider an indirect interest in a VIE held by related party under common control on a proportionate basis. The new standard is effective interim and annual periods beginning after December 15, 2019, with early adoption permitted. The Company adopted this guidance as of January 1, 2020 and the adoption did not have an impact on the Company’s consolidated financial statements. Credit Losses In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), and a subsequent amendment to the initial guidance, ASU 2018-19 Codification Improvements to Topic 326, Financial Instruments—Credit Losses (collectively, Topic 326). Topic 326 requires measurement and recognition of expected credit losses for financial assets held, which include, but are not limited to, trade and other receivables. The new standard is effective for fiscal years beginning after December 15, 2019, The Company adopted this guidance as of January 1, 2020 and the adoption did not have a material impact on the Company’s consolidated financial statements. In April 2019, the FASB issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments – Credit Losses, Topic 815, Derivatives, and Hedging, and Topic 825, Financial Instruments. The improvements to Topic 815, among other things, clarifies some areas around partial-term fair value hedges, interest rate risk, the amortization of fair value hedge basis adjustments and their disclosure, and some clarification of matters related to the transitioning to ASU. 2017-12, which was adopted by the Company during the year ended December 31, 2018. The improvements to Topic 326 clarifies certain aspects surrounding accounting for credit losses in connection with the Company’s receivables. These include that the Company should include anticipated recoveries in its calculation of credit losses. For those that have already adopted ASU No. 2017-12, the new standard is effective the first annual period beginning after the issuance date of ASU No. 2019-04, or as of January 1, 2020 for the Company, with early adoption permitted. The Company adopted this guidance as of January 1, 2020 and the adoption did not have a material impact on the Company’s consolidated financial statements. Income Taxes In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes, eliminates certain exceptions within ASC 740, Income Taxes, and clarifies certain aspects of the current guidance to promote consistency among reporting entities. ASU 2019-12 is effective for the Company for the fiscal year beginning after December 15, 2020. The Company is currently evaluating the impacts of the provisions of ASU 2019-12 on its consolidated financial statements and disclosures. Others In March 2020, the FASB issued ASU 2020-04 Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. ASU 2020-04 provides optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. Companies can apply the ASU immediately, however the guidance will only be available until December 31, 2022. The Company is currently evaluating the impact that adopting this new accounting standard will have on its condensed consolidated financial statements and related disclosures.
Earnings Per Share	Earnings Per Share Basic earnings per share is calculated using the Company’s weighted-average outstanding common shares, including vested restricted shares. When the effects are not anti-dilutive, diluted earnings per share is calculated using the weighted-average outstanding common shares; the dilutive effect of convertible preferred stock, under the “if converted” method; and the treasury stock method with regard to warrants and stock options; all as determined under the treasury stock method.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Accounts Receivable, Allowance for Credit Loss	Changes in the allowance for credit losses for the three months ended March 31, 2020 and 2019 are as follows: March 31, 2020 March 31, 2019 Allowance for credit loss, beginning of period $ 2,260 $ 2,765 Charges to costs and expenses, net 49 77 Account write-offs and other (189) (29) Allowance for credit loss, end of period $ 2,120 $ 2,813

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	3 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Summary of Disaggregation of Revenue	The following table provides information about disaggregated revenue by line of business, reportable segments, and geographical region for the three months ended March 31, 2020 and 2019. US Regions U.S. Federal Canada Non-Solar DG All Other Total Line of Business Three Months Ended March 31, 2020 Project revenue $ 71,493 $ 56,114 $ 8,864 $ 2,371 $ 5,587 $ 144,429 O&M revenue 4,352 11,626 9 2,015 60 18,062 Energy assets 8,554 719 663 17,986 300 28,222 Other 328 286 1,856 352 18,878 21,700 Total revenues $ 84,727 $ 68,745 $ 11,392 $ 22,724 $ 24,825 $ 212,413 Three Months Ended March 31, 2019 Project revenue $ 45,704 $ 32,353 $ 5,234 $ 1,074 $ 3,067 $ 87,432 O&M revenue 3,318 9,858 — 2,035 — 15,211 Energy assets 6,021 643 320 17,699 302 24,985 Other 554 203 1,594 422 19,711 22,484 Total revenues $ 55,597 $ 43,057 $ 7,148 $ 21,230 $ 23,080 $ 150,112 US Regions U.S. Federal Canada Non-Solar DG All Other Total Geographical Regions Three Months Ended March 31, 2020 United States $ 84,727 $ 68,745 $ 896 $ 22,724 $ 18,847 $ 195,939 Canada — — 10,496 — 57 10,553 Other — — — — 5,921 5,921 Total revenues $ 84,727 $ 68,745 $ 11,392 $ 22,724 $ 24,825 $ 212,413 Three Months Ended March 31, 2019 United States $ 55,597 $ 43,057 $ 702 $ 21,230 $ 18,647 $ 139,233 Canada — — 6,446 — 65 6,511 Other — — — — 4,368 4,368 Total revenues $ 55,597 $ 43,057 $ 7,148 $ 21,230 $ 23,080 $ 150,112
Summary of Contract with Customer, Asset and Liability	The following table provides information about receivables, contract assets and contract liabilities from contracts with customers: March 31, 2020 December 31, 2019 Accounts receivable, net $ 110,742 $ 95,863 Accounts receivable retainage, net 21,265 16,976 Contract Assets: Costs and estimated earnings in excess of billings 189,566 202,243 Contract Liabilities: Billings in excess of cost and estimated earnings 30,670 32,178 March 31, 2019 December 31, 2018 Accounts receivable, net $ 81,896 $ 85,985 Accounts receivable retainage, net 14,762 13,516 Contract Assets: Costs and estimated earnings in excess of billings 92,264 86,842 Contract Liabilities: Billings in excess of cost and estimated earnings 31,483 30,706

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Carrying Value of Goodwill Attributable to Each Reportable Segment	The changes in the carrying value of goodwill attributable to each reportable segment are as follows: U.S. Regions U.S. Federal Canada Non-solar DG Other Total Balance, December 31, 2019 $ 26,705 $ 3,981 $ 3,369 $ — $ 24,359 $ 58,414 Currency effects — — (274) — (399) (673) Balance, March 31, 2020 $ 26,705 $ 3,981 $ 3,095 $ — $ 23,960 $ 57,741 Accumulated Goodwill Impairment Balance, December 31, 2019 $ — $ — $ (1,016) $ — $ — $ (1,016) Balance, March 31, 2020 $ — $ — $ (1,016) $ — $ — $ (1,016)
Schedule of Gross Carrying Amount and Accumulated Amortization of Intangible Assets	The gross carrying amount and accumulated amortization of intangible assets are as follows: As of March 31, As of December 31, 2020 2019 Gross Carrying Amount Customer contracts $ 7,749 $ 7,904 Customer relationships 12,449 12,749 Non-compete agreements 2,995 3,037 Technology 2,691 2,732 Trade names 539 544 26,423 26,966 Accumulated Amortization Customer contracts 7,711 7,844 Customer relationships 11,112 11,236 Non-compete agreements 2,995 3,037 Technology 2,669 2,704 Trade names 528 531 25,015 25,352 Intangible assets, net $ 1,408 $ 1,614

Energy Assets (Tables)

Energy Assets (Tables)	3 Months Ended
	Mar. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Energy Assets	Energy assets consist of the following: March 31, December 31, 2020 2019 Energy assets $ 793,215 $ 767,331 Less - accumulated depreciation and amortization (196,723) (187,870) Energy assets, net $ 596,492 $ 579,461
Schedule of Financing Lease Assets	Included in energy assets are financing lease assets and accumulated depreciation of financing lease assets. Financing lease assets consist of the following: March 31, December 31, 2020 2019 Financing lease assets $ 42,402 $ 42,402 Less - accumulated depreciation and amortization (6,800) (6,268) Financing lease assets, net $ 35,602 $ 36,134 As of January 1, 2019 As Reported 842 Adjustment Adjusted Balances Operating Leases: Operating lease assets $ — $ 31,639 $ 31,639 Current portions of operating lease liabilities — 5,084 5,084 Long-term portions of operating lease liabilities — 28,480 28,480 Total operating lease liabilities $ — $ 33,564 $ 33,564 Weighted-average remaining lease term 10 years Weighted-average discount rate 6.0 % Financing Leases: Energy assets, net $ 38,263 $ — $ 38,263 Current portions of financing lease liabilities 4,956 — 4,956 Long-term financing lease liabilities, net of current portions and of deferred financing fees 28,407 — 28,407 Total financing lease liabilities $ 33,363 $ — $ 33,363 Weighted-average remaining lease term 18 years Weighted-average discount rate 11.7 % Supplemental balance sheet information related to leases at March 31, 2020 and December 31, 2019 is as follows: March 31, 2020 December 31, 2019 Operating Leases: Operating lease assets $ 32,444 $ 32,791 Current operating lease liabilities 5,360 5,802 Long-term portions of operating lease liabilities 29,104 29,101 Total operating lease liabilities $ 34,464 $ 34,903 Weighted-average remaining lease term 11 years 11 years Weighted-average discount rate 6.4 % 6.3 % Financing Leases: Energy assets, net $ 35,602 $ 36,134 Current portions of financing lease liabilities 4,906 4,997 Long-term financing lease liabilities, less current portions and net of deferred financing fees 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Weighted-average remaining lease term 17 years 17 years Weighted-average discount rate 11.8 % 11.8 %

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Reconciliation of Gross Unrecognized Tax Benefits	A reconciliation of the beginning and ending balances of the total amounts of gross unrecognized tax benefits is as follows: Gross Unrecognized Tax Benefits Balance, December 31, 2019 $ 400 Additions for prior year tax positions — Settlements with tax authorities — Reductions of prior year tax positions — Balance, March 31, 2020 $ 400

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Schedule of Assets and Liabilities, Lessee	Included in energy assets are financing lease assets and accumulated depreciation of financing lease assets. Financing lease assets consist of the following: March 31, December 31, 2020 2019 Financing lease assets $ 42,402 $ 42,402 Less - accumulated depreciation and amortization (6,800) (6,268) Financing lease assets, net $ 35,602 $ 36,134 As of January 1, 2019 As Reported 842 Adjustment Adjusted Balances Operating Leases: Operating lease assets $ — $ 31,639 $ 31,639 Current portions of operating lease liabilities — 5,084 5,084 Long-term portions of operating lease liabilities — 28,480 28,480 Total operating lease liabilities $ — $ 33,564 $ 33,564 Weighted-average remaining lease term 10 years Weighted-average discount rate 6.0 % Financing Leases: Energy assets, net $ 38,263 $ — $ 38,263 Current portions of financing lease liabilities 4,956 — 4,956 Long-term financing lease liabilities, net of current portions and of deferred financing fees 28,407 — 28,407 Total financing lease liabilities $ 33,363 $ — $ 33,363 Weighted-average remaining lease term 18 years Weighted-average discount rate 11.7 % Supplemental balance sheet information related to leases at March 31, 2020 and December 31, 2019 is as follows: March 31, 2020 December 31, 2019 Operating Leases: Operating lease assets $ 32,444 $ 32,791 Current operating lease liabilities 5,360 5,802 Long-term portions of operating lease liabilities 29,104 29,101 Total operating lease liabilities $ 34,464 $ 34,903 Weighted-average remaining lease term 11 years 11 years Weighted-average discount rate 6.4 % 6.3 % Financing Leases: Energy assets, net $ 35,602 $ 36,134 Current portions of financing lease liabilities 4,906 4,997 Long-term financing lease liabilities, less current portions and net of deferred financing fees 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Weighted-average remaining lease term 17 years 17 years Weighted-average discount rate 11.8 % 11.8 %
Schedule of Lease Costs	The costs related to our leases are as follows: Three Months Ended March 31, 2020 Three Months Ended March 31, 2019 Operating Lease: Operating lease costs $ 1,826 $ 1,838 Financing Lease: Amortization expense 532 532 Interest on lease liabilities 801 949 Total lease costs $ 3,159 $ 3,319
Schedule of Finance Lease Liability Maturity	The Company’s estimated minimum future lease obligations under our leases are as follows: Operating Leases Financing Leases Year ended December 31, 2020 $ 5,816 $ 7,852 2021 6,506 6,792 2022 5,895 5,178 2023 4,607 3,676 2024 3,791 2,565 Thereafter 22,723 24,080 Total minimum lease payments $ 49,338 $ 50,143 Less: interest 14,874 21,765 Present value of lease liabilities $ 34,464 $ 28,378
Schedule of Operating Lease Liability Maturity	The Company’s estimated minimum future lease obligations under our leases are as follows: Operating Leases Financing Leases Year ended December 31, 2020 $ 5,816 $ 7,852 2021 6,506 6,792 2022 5,895 5,178 2023 4,607 3,676 2024 3,791 2,565 Thereafter 22,723 24,080 Total minimum lease payments $ 49,338 $ 50,143 Less: interest 14,874 21,765 Present value of lease liabilities $ 34,464 $ 28,378
Schedule of Amount Related to Sale Leasebacks	A summary of amounts related to sale leasebacks in the Company’s condensed consolidated balance sheets is as follows: March 31, December 31, 2020 2019 Financing lease assets, net $ 35,602 $ 36,134 Deferred loss, short-term, net 115 115 Deferred loss, long-term, net 1,773 1,801 Total deferred loss $ 1,888 $ 1,916 Financing lease liabilities, short-term 4,906 4,997 Financing lease liabilities, long-term 23,472 23,500 Total financing lease liabilities $ 28,378 $ 28,497 Deferred gain, short-term, net 345 345 Deferred gain, long-term, net 5,379 5,463 Total deferred gain $ 5,724 $ 5,808

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Liabilities Measured on a Recurring Basis	The following table presents the input level used to determine the fair values of the Company’s financial instruments measured at fair value on a recurring basis: Fair Value as of March 31, December 31, Level 2020 2019 Assets: Interest rate swap instruments 2 $ — $ 15 Commodity swap instruments 2 246 198 Total assets $ 246 $ 213 Liabilities: Interest rate swap instruments 2 $ 10,882 $ 6,236 Interest make-whole provisions 2 733 918 Contingent consideration 3 678 678 Total liabilities $ 12,293 $ 7,832
Schedule of Changes In Fair Value Of Contingent Liabilities Classified as Level 3	The following table sets forth a summary of changes in fair value of contingent liabilities classified as Level 3 for the three months ended March 31, 2020 and March 31, 2019: Three Months Ended Three Months Ended March 31, 2020 March 31, 2019 Contingent consideration liabilities balance at December 31, 2019 and 2018 $ 678 $ 600 Changes in the fair value of contingent consideration obligation — 25 Contingent consideration liabilities balance at March 31, 2020 and 2019 $ 678 $ 625
Schedule of Fair Value and Carrying Value for Company's Long-Term Debt	Based on the analysis performed, the fair value and the carrying value of the Company’s long-term debt, excluding financing leases, are as follows: As of March 31, 2020 As of December 31, 2019 Fair Value Carrying Value Fair Value Carrying Value Long-term debt (Level 2) $ 332,683 $ 326,459 $ 309,377 $ 307,508

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Fair Value of Derivative Instruments	At March 31, 2020 and December 31, 2019, the following table presents information about the fair value amounts of the Company’s derivative instruments are as follows: Derivatives as of March 31, 2020 December 31, 2019 Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives Designated as Hedging Instruments: Interest rate swap contracts Other assets $ — Other assets $ 15 Interest rate swap contracts Other liabilities 10,846 Other liabilities 6,210 Derivatives Not Designated as Hedging Instruments: Interest rate swap contracts Other liabilities $ 36 Other liabilities $ 26 Commodity swap contracts Other assets 246 Other assets 198 Commodity swap contracts Other liabilities — Other liabilities — Interest make-whole provisions Other liabilities 733 Other liabilities 918 Other Derivatives Classification Effective Date Expiration Date Fair Value ($) Interest make-whole provisions Liability June/August 2018 December 2038 $ 733
Schedule of Derivative Effect on Consolidated Statement of Income (Loss)	The following tables present information about the effects of the Company’s derivative instruments on the condensed consolidated statements of income and condensed consolidated statements of comprehensive income: Location of (Gain) Loss Recognized in Net Income Amount of (Gain) Loss Recognized in Net Income Three Months Ended March 31, 2020 2019 Derivatives Designated as Hedging Instruments: Interest rate swap contracts Other expenses, net $ 99 $ (49) Derivatives Not Designated as Hedging Instruments: Interest rate swap contracts Other expenses, net $ 10 $ — Commodity swap contracts Other expenses, net (48) — Interest make-whole provision Other expenses, net (185) (723)
Schedule of Derivative Instruments Effect on Comprehensive Income (Loss)	Three Months Ended March 31, 2020 Derivatives Designated as Hedging Instruments: Accumulated loss in AOCI at the beginning of the period $ (4,742) Unrealized loss recognized in AOCI (3,564) Loss reclassified from AOCI to other expenses, net 99 Accumulated loss in AOCI at the end of the period $ (8,207)
Schedule of Active Derivative Instruments	The following tables present a listing of all the Company’s active derivative instruments as of March 31, 2020: Active Interest Rate Swap Effective Date Expiration Date Initial Notional Amount ($) Status 11-Year, 5.77% Fixed October 2018 October 2029 $ 9,200 Designated 15-Year, 5.24% Fixed June 2018 June 2033 10,000 Designated 3-Year, 2.46% Fixed March 2018 December 2020 17,100 Not Designated 10-Year, 4.74% Fixed June 2017 December 2027 14,100 Designated 15-Year, 3.26% Fixed February 2023 December 2038 14,084 Designated 7-Year, 2.19% Fixed February 2016 February 2023 20,746 Designated 8-Year, 3.70% Fixed March 2020 June 2028 14,643 Designated 8-Year, 3.70% Fixed March 2020 June 2028 10,734 Designated 15-Year, 5.30% Fixed February 2006 February 2021 3,256 Designated 15.5-Year, 5.40% Fixed September 2008 March 2024 13,081 Designated Active Commodity Swap Effective Date Expiration Date Initial Notional Amount (Volume) Commodity Measurement Status 1-Year, $2.68 MMBtu Fixed May 2019 April 2020 437,004 MMBtus Not Designated 1-Year, $2.70 MMBtu Fixed May 2020 April 2021 435,810 MMBtus Not Designated

Investment Funds And Other Va_2

Investment Funds And Other Variable Interest Entities (Tables)	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Variable Interest Entities	A summary of amounts related to the investment funds in the Company’s condensed consolidated balance sheets is as follows: March 31, December 31, 2020 (1) 2019 (1) Cash and cash equivalents $ 5,789 $ 4,666 Restricted cash 586 586 Accounts receivable, net 462 532 Costs and estimated earnings in excess of billings 1,355 1,125 Prepaid expenses and other current assets 80 108 Total VIE current assets 8,272 7,017 Property and equipment, net 1,266 1,266 Energy assets, net 145,410 142,456 Operating lease assets 6,411 6,511 Other assets 1,660 1,662 Total VIE assets $ 163,019 $ 158,912 Current portions of long-term debt and financing lease liabilities $ 2,234 $ 2,252 Accounts payable 2,670 2,006 Accrued expenses and other current liabilities 1,623 2,203 Current portions of operating lease liabilities 106 102 Total VIE current liabilities 6,633 6,563 Long-term debt and financing lease liabilities, less current portions and net of deferred financing fees 24,214 24,654 Long-term portions of operating lease liabilities 6,173 6,180 Other liabilities 1,004 1,171 Total VIE liabilities $ 38,024 $ 38,568 (1) The amounts in the above table are reflected in Note 1 on the Company’s condensed consolidated balance sheets. See the Company’s condensed consolidated balance sheets for additional information.

Earnings Per Share and Other _2

Earnings Per Share and Other Equity Related Information (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Basic earnings per share is calculated using the Company’s weighted-average outstanding common shares, including vested restricted shares. When the effects are not anti-dilutive, diluted earnings per share is calculated using the weighted-average outstanding common shares; the dilutive effect of convertible preferred stock, under the “if converted” method; and the treasury stock method with regard to warrants and stock options; all as determined under the treasury stock method. Three Months Ended March 31, 2020 2019 Net income attributable to common shareholders $ 6,201 $ 4,147 Basic weighted-average shares outstanding 47,384 46,293 Effect of dilutive securities: Stock options 1,113 1,361 Diluted weighted-average shares outstanding 48,497 47,654

Business Segment Information (T

Business Segment Information (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Schedule of Operational Results by Business Segments	An analysis of the Company’s business segment information and reconciliation to the condensed consolidated financial statements is as follows: U.S. Regions U.S. Federal Canada Non-Solar DG All Other Total Consolidated Three Months Ended March 31, 2020 Revenues $ 84,727 $ 68,745 $ 11,392 $ 22,724 $ 24,825 $ 212,413 Interest income 36 40 — 14 — 90 Interest expense 1,481 746 172 1,045 15 3,459 Depreciation and amortization of intangible assets 2,763 1,017 391 5,287 376 9,834 Unallocated corporate activity — — — — — (10,346) Income before taxes, excluding unallocated corporate activity 3,723 7,094 (221) 1,669 2,212 14,477 Three Months Ended March 31, 2019 Revenues $ 55,597 $ 43,057 $ 7,148 $ 21,230 $ 23,080 $ 150,112 Interest income 63 49 — 21 — 133 Interest expense 857 210 164 1,577 — 2,808 Depreciation and amortization of intangible assets 2,182 817 275 5,216 348 8,838 Unallocated corporate activity — — — — — (8,008) Income before taxes, excluding unallocated corporate activity (278) 5,621 (289) 1,381 4,701 11,136

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	As of March 31, 2020 and December 31, 2019, the Company’s debt comprised the following: Commencement Date Maturity Date Acceleration Clause (2) Rate as of March 31, 2020 March 31, 2020 December 31, 2019 Senior secured credit facility, interest at varying rates monthly in arrears June 2015 June 2024 NA 4.36 % $ 142,022 $ 112,216 Variable rate term loan payable in semi-annual installments January 2006 February 2021 Yes 3.70 % 625 625 Variable rate term loan payable in semi-annual installments January 2006 June 2024 Yes 3.45 % 6,609 6,609 Term loan payable in quarterly installments March 2011 March 2021 Yes 7.25 % 666 831 Term loan payable in monthly installments October 2011 June 2028 NA 6.11 % 3,314 3,649 Variable rate term loan payable in quarterly installments October 2012 May 2020 NA 4.95 % 27,617 28,217 Variable rate term loan payable in quarterly installments September 2015 March 2023 NA 4.20 % 15,995 15,976 Term loan payable in quarterly installments August 2016 July 2031 NA 4.95 % 3,392 3,769 Term loan payable in quarterly installments March 2017 March 2028 NA 5.00 % 3,416 3,521 Term loan payable in monthly installments April 2017 April 2027 NA 4.50 % 21,823 22,553 Term loan payable in quarterly installments April 2017 February 2034 NA 5.61 % 2,487 2,706 Variable rate term loan payable in quarterly installments June 2017 December 2027 NA 3.90 % 11,740 11,740 Variable rate term loan payable in quarterly installments February 2018 August 2022 Yes 8.95 % 12,436 15,645 Term loan payable in quarterly installments June 2018 December 2038 Yes 5.15 % 28,073 28,583 Variable rate term loan payable in semi-annual installments June 2018 June 2033 Yes 3.50 % 9,003 9,003 Variable rate term loan payable in monthly/quarterly installments October 2018 October 2029 Yes 3.94 % 8,923 9,092 Long term finance liability in semi-annual installments (3) July 2019 July 2039 NA 0.28 % 3,785 3,841 Long term finance liability in semi-annual installments (3) November 2019 November 2039 NA — % 6,970 8,794 Term loan payable in quarterly installments December 2019 December 2021 Yes 6.500 % 24,167 27,226 Financing leases (1) 28,378 28,497 $ 361,441 $ 343,093 Less - current maturities 69,282 69,969 Less - deferred financing fees 6,606 6,943 Long term debt and financing lease liabilities $ 285,553 $ 266,181 (1) Financing leases do not include approximately $21,765 in future interest payments (2) These agreements have acceleration causes that, in the event of default, as defined, the payee has the option to accelerate payment terms and make due the remaining principal and the required interest balance according to the agreement (3) These agreements are sale-leaseback arrangements that provides for the sale of solar PV projects to a third party investor and the simultaneous leaseback of the projects. In accordance with Topic 842, Leases, these transactions are accounted for as a

(Details)

(Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
CARES Act, payroll taxes to be paid in 2021 and 2022	$ 5,000
CARES Act, tax benefit associated with net operating loss	2,000
CARES Act, tax refund	$ 1,300

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss, beginning of period	$ 2,260	$ 2,765
Charges to costs and expenses, net	49	77
Account write-offs and other	(189)	(29)
Allowance for credit loss, end of period	$ 2,120	$ 2,813

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Accounting Policies [Abstract]
Restricted cash non-current	$ 24,333	$ 20,920

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Recent Accounting Pronouncements (Details) $ in Thousands	Jan. 01, 2019USD ($)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative impact from the adoption of ASU	$ 217

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 212,413	$ 150,112
United States
Disaggregation of Revenue [Line Items]
Revenues	195,939	139,233
Canada
Disaggregation of Revenue [Line Items]
Revenues	10,553	6,511
Other
Disaggregation of Revenue [Line Items]
Revenues	5,921	4,368
Project revenue
Disaggregation of Revenue [Line Items]
Revenues	144,429	87,432
O&M revenue
Disaggregation of Revenue [Line Items]
Revenues	18,062	15,211
Energy assets
Disaggregation of Revenue [Line Items]
Revenues	28,222	24,985
Other
Disaggregation of Revenue [Line Items]
Revenues	21,700	22,484
US Regions
Disaggregation of Revenue [Line Items]
Revenues	84,727	55,597
US Regions | United States
Disaggregation of Revenue [Line Items]
Revenues	84,727	55,597
US Regions | Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0
US Regions | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0
US Regions | Project revenue
Disaggregation of Revenue [Line Items]
Revenues	71,493	45,704
US Regions | O&M revenue
Disaggregation of Revenue [Line Items]
Revenues	4,352	3,318
US Regions | Energy assets
Disaggregation of Revenue [Line Items]
Revenues	8,554	6,021
US Regions | Other
Disaggregation of Revenue [Line Items]
Revenues	328	554
U.S. Federal
Disaggregation of Revenue [Line Items]
Revenues	68,745	43,057
U.S. Federal | United States
Disaggregation of Revenue [Line Items]
Revenues	68,745	43,057
U.S. Federal | Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0
U.S. Federal | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0
U.S. Federal | Project revenue
Disaggregation of Revenue [Line Items]
Revenues	56,114	32,353
U.S. Federal | O&M revenue
Disaggregation of Revenue [Line Items]
Revenues	11,626	9,858
U.S. Federal | Energy assets
Disaggregation of Revenue [Line Items]
Revenues	719	643
U.S. Federal | Other
Disaggregation of Revenue [Line Items]
Revenues	286	203
Canada
Disaggregation of Revenue [Line Items]
Revenues	11,392	7,148
Canada | United States
Disaggregation of Revenue [Line Items]
Revenues	896	702
Canada | Canada
Disaggregation of Revenue [Line Items]
Revenues	10,496	6,446
Canada | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0
Canada | Project revenue
Disaggregation of Revenue [Line Items]
Revenues	8,864	5,234
Canada | O&M revenue
Disaggregation of Revenue [Line Items]
Revenues	9	0
Canada | Energy assets
Disaggregation of Revenue [Line Items]
Revenues	663	320
Canada | Other
Disaggregation of Revenue [Line Items]
Revenues	1,856	1,594
Non-Solar DG
Disaggregation of Revenue [Line Items]
Revenues	22,724	21,230
Non-Solar DG | United States
Disaggregation of Revenue [Line Items]
Revenues	22,724	21,230
Non-Solar DG | Canada
Disaggregation of Revenue [Line Items]
Revenues	0	0
Non-Solar DG | Other
Disaggregation of Revenue [Line Items]
Revenues	0	0
Non-Solar DG | Project revenue
Disaggregation of Revenue [Line Items]
Revenues	2,371	1,074
Non-Solar DG | O&M revenue
Disaggregation of Revenue [Line Items]
Revenues	2,015	2,035
Non-Solar DG | Energy assets
Disaggregation of Revenue [Line Items]
Revenues	17,986	17,699
Non-Solar DG | Other
Disaggregation of Revenue [Line Items]
Revenues	352	422
All Other
Disaggregation of Revenue [Line Items]
Revenues	24,825	23,080
All Other | United States
Disaggregation of Revenue [Line Items]
Revenues	18,847	18,647
All Other | Canada
Disaggregation of Revenue [Line Items]
Revenues	57	65
All Other | Other
Disaggregation of Revenue [Line Items]
Revenues	5,921	4,368
All Other | Project revenue
Disaggregation of Revenue [Line Items]
Revenues	5,587	3,067
All Other | O&M revenue
Disaggregation of Revenue [Line Items]
Revenues	60	0
All Other | Energy assets
Disaggregation of Revenue [Line Items]
Revenues	300	302
All Other | Other
Disaggregation of Revenue [Line Items]
Revenues	$ 18,878	$ 19,711

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Contract Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2020		Dec. 31, 2019		Mar. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Accounts receivable, net	$ 110,742	[1]	$ 95,863	[1]	$ 81,896	$ 85,985
Accounts receivable retainage, net	21,265		16,976		14,762	13,516
Contract Assets:
Costs and estimated earnings in excess of billings	189,566	[1]	202,243	[1]	92,264	86,842
Contract Liabilities:
Billings in excess of cost and estimated earnings	$ 30,670		$ 32,178		$ 31,483	$ 30,706
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Percentage of revenue recognized over time	91.00%		89.00%
Contract with customer, liability, noncurrent	$ 5,320,000		$ 5,560,000
Contract with customer, asset, reclassified to receivable	152,612,000	$ 90,895,000
Contract with customer, asset, revenue recognized	137,596,000	90,344,000
Contract with customer, liability, revenue recognized	19,552,000	24,095,000
Contract with customer, liability, billings	15,651,000	18,929,000
Revenue, remaining performance obligation	$ 2,181,643,000
Revenue, remaining performance obligation, percentage	26.00%
Capitalized contract cost, gross	$ 1,735,000		1,735,000
Capitalized project development costs, noncurrent	697,000		217,000
Capitalized contract cost, project development costs	1,635,000		$ 2,777,000
Capitalized contract cost, impairment loss	$ 0	$ 0
Minimum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivable retainage percentage	5.00%
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivable retainage percentage	10.00%

Business Acquisitions and Rel_2

Business Acquisitions and Related Transactions - Additional Information (Details) - Solar Photovoltaic Projects	3 Months Ended
	Mar. 31, 2020
Minimum
Business Acquisition [Line Items]
Estimated useful life	1 year
Maximum
Business Acquisition [Line Items]
Estimated useful life	15 years

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Balance, December 31, 2019	$ 58,414
Currency effects	(673)
Balance, March 31, 2020	57,741
Accumulated goodwill impairment	(1,016)	$ (1,016)
Operating Segments | U.S. Regions
Goodwill [Roll Forward]
Balance, December 31, 2019	26,705
Currency effects	0
Balance, March 31, 2020	26,705
Accumulated goodwill impairment	0	0
Operating Segments | U.S. Federal
Goodwill [Roll Forward]
Balance, December 31, 2019	3,981
Currency effects	0
Balance, March 31, 2020	3,981
Accumulated goodwill impairment	0	0
Operating Segments | Canada
Goodwill [Roll Forward]
Balance, December 31, 2019	3,369
Currency effects	(274)
Balance, March 31, 2020	3,095
Accumulated goodwill impairment	(1,016)	(1,016)
Operating Segments | Non-solar DG
Goodwill [Roll Forward]
Balance, December 31, 2019	0
Currency effects	0
Balance, March 31, 2020	0
Accumulated goodwill impairment	0	0
Operating Segments | Other
Goodwill [Roll Forward]
Balance, December 31, 2019	24,359
Currency effects	(399)
Balance, March 31, 2020	23,960
Accumulated goodwill impairment	$ 0	$ 0

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Reporting units, fair value in excess of carrying amounts			15.00%
Gross Carrying Amount	$ 26,423		$ 26,966
Accumulated Amortization	25,015		25,352
Intangible assets, net	1,408		1,614
Amortization of intangible assets	179	$ 213
Customer contracts
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,749		7,904
Accumulated Amortization	7,711		7,844
Amortization of intangible assets	22	23
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	12,449		12,749
Accumulated Amortization	11,112		11,236
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,995		3,037
Accumulated Amortization	2,995		3,037
Technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,691		2,732
Accumulated Amortization	2,669		2,704
Trade names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	539		544
Accumulated Amortization	528		$ 531
Other intangible assets
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 154	$ 201
Minimum | Customer contracts
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets useful life	1 year
Minimum | Other intangible assets
Finite-Lived Intangible Assets [Line Items]
All other acquired intangible assets useful life	4 years
Maximum | Customer contracts
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets useful life	5 years
Maximum | Other intangible assets
Finite-Lived Intangible Assets [Line Items]
All other acquired intangible assets useful life	15 years

Energy Assets - Energy Assets (

Energy Assets - Energy Assets (Details) - USD ($) $ in Thousands		Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Energy assets, net	[1]	$ 596,492	$ 579,461
Energy Assets
Property, Plant and Equipment [Line Items]
Energy assets		793,215	767,331
Less - accumulated depreciation and amortization		(196,723)	(187,870)
Energy assets, net		$ 596,492	$ 579,461
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Energy Assets - Financing Lease

Energy Assets - Financing Lease Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Financing lease assets	$ 42,402	$ 42,402
Less - accumulated depreciation and amortization	(6,800)	(6,268)
Financing lease assets, net	$ 35,602	$ 36,134	$ 38,263

Energy Assets - Narrative (Deta

Energy Assets - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)project	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)project	Dec. 31, 2018USD ($)
Business Acquisition [Line Items]
Depreciation and amortization expense	$ 9,299	$ 8,407
Finance lease right-of-use assets, amortization expense	532	532
Interest costs capitalized	$ 862	788
Number of ESPC projects included in energy assets that the Company owns and operates | project	3		3
Contract with customer, liability	$ 30,670	31,483	$ 32,178	$ 30,706
Contract with customer, current liability	25,350		26,618
Asset retirement obligation recorded in project assets	1,431
Asset retirement obligation liability recorded in accrued expenses	1,559
Depreciation of property and equipment	833	619
ARO accretion expense	21	9
ARO Asset
Business Acquisition [Line Items]
Depreciation of property and equipment	19	$ 11
Solar Projects 2020
Business Acquisition [Line Items]
Contingent consideration, liability	$ 6,693
Number of projects under definitive agreement to acquire | project	10
Solar Projects 2020, Additional Projects
Business Acquisition [Line Items]
Fair value of consideration	$ 13,902
Amount paid to developers of projects	366
Energy Assets
Business Acquisition [Line Items]
Contract with customer, liability	11,105		10,243
Energy Assets | Accrued Expenses And Other Current Liabilities
Business Acquisition [Line Items]
Contract with customer, current liability	$ 217		$ 827

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax (benefit) provision	$ (2,503)	$ 257
Effective tax rate, percentage	(60.60%)	8.20%
Gross unrecognized tax benefits	$ 400		$ 400
Unrecognized tax benefits, if recognized would affect effective income tax rate	$ 80		$ 80

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, December 31, 2019	$ 400
Additions for prior year tax positions	0
Settlements with tax authorities	0
Reductions of prior year tax positions	0
Balance, March 31, 2020	$ 400

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($)	Jan. 01, 2019	Mar. 31, 2020		Mar. 31, 2019	Jan. 31, 2020	Dec. 31, 2019	[1]	Sep. 30, 2018
Lessee, Lease, Description [Line Items]
Operating lease assets	$ 31,639,000	$ 32,444,000	[1]			$ 32,791,000
Current operating lease liabilities	5,084,000	5,360,000	[1]			5,802,000
Long-term portions of operating lease liabilities	28,480,000	29,104,000	[1]			$ 29,101,000
Operating lease impairment	0
Operating leases revenue		2,245,000		$ 2,224,000
Net amortization expense		55,000		$ 38,000
Maximum combined funding amount					$ 150,000,000			$ 100,000,000
Available funding under lending commitment		$ 131,000,000
842 Adjustment
Lessee, Lease, Description [Line Items]
Operating lease assets	31,639,000
Current operating lease liabilities	5,084,000
Long-term portions of operating lease liabilities	$ 28,480,000
Minimum
Lessee, Lease, Description [Line Items]
Operating lease renewal term		6 months
Maximum
Lessee, Lease, Description [Line Items]
Operating lease renewal term		7 years
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Leases - Adoption of New Leasin

Leases - Adoption of New Leasing Standard (Details) - USD ($) $ in Thousands	Mar. 31, 2020		Dec. 31, 2019		Jan. 01, 2019
Operating Leases:
Operating lease assets	$ 32,444	[1]	$ 32,791	[1]	$ 31,639
Current portions of operating lease liabilities	5,360	[1]	5,802	[1]	5,084
Long-term portions of operating lease liabilities	29,104	[1]	29,101	[1]	28,480
Total operating lease liabilities	$ 34,464		$ 34,903		$ 33,564
Operating lease, weighted-average remaining lease term	11 years		11 years		10 years
Operating lease, weighted-average discount rate	6.40%		6.30%		6.00%
Financing Leases:
Energy assets, net	$ 35,602		$ 36,134		$ 38,263
Current portions of financing lease liabilities	4,906		4,997		4,956
Long-term financing lease liabilities, less current portions and net of deferred financing fees	23,472		23,500		28,407
Total financing lease liabilities	$ 28,378		$ 28,497		$ 33,363
Financing lease, weighted-average remaining lease term	17 years		17 years		18 years
Financing lease, weighted-average discount rate	11.80%		11.80%		11.70%
As Reported
Operating Leases:
Operating lease assets					$ 0
Current portions of operating lease liabilities					0
Long-term portions of operating lease liabilities					0
Total operating lease liabilities					0
Financing Leases:
Energy assets, net					38,263
Current portions of financing lease liabilities					4,956
Long-term financing lease liabilities, less current portions and net of deferred financing fees					28,407
Total financing lease liabilities					33,363
842 Adjustment
Operating Leases:
Operating lease assets					31,639
Current portions of operating lease liabilities					5,084
Long-term portions of operating lease liabilities					28,480
Total operating lease liabilities					33,564
Financing Leases:
Energy assets, net					0
Current portions of financing lease liabilities					0
Long-term financing lease liabilities, less current portions and net of deferred financing fees					0
Total financing lease liabilities					$ 0
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheet Information Related to Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2020		Dec. 31, 2019		Jan. 01, 2019
Operating Leases:
Operating lease assets	$ 32,444	[1]	$ 32,791	[1]	$ 31,639
Current operating lease liabilities	5,360	[1]	5,802	[1]	5,084
Long-term portions of operating lease liabilities	29,104	[1]	29,101	[1]	28,480
Total operating lease liabilities	$ 34,464		$ 34,903		$ 33,564
Operating lease, weighted-average remaining lease term	11 years		11 years		10 years
Operating lease, weighted-average discount rate	6.40%		6.30%		6.00%
Financing Leases:
Energy assets, net	$ 35,602		$ 36,134		$ 38,263
Current portions of financing lease liabilities	4,906		4,997		4,956
Long-term financing lease liabilities, less current portions and net of deferred financing fees	23,472		23,500		28,407
Total financing lease liabilities	$ 28,378		$ 28,497		$ 33,363
Financing lease, weighted-average remaining lease term	17 years		17 years		18 years
Financing lease, weighted-average discount rate	11.80%		11.80%		11.70%
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Leases - Lease Cost (Details)

Leases - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating Leases:
Operating lease costs	$ 1,826	$ 1,838
Financing Leases:
Amortization expense	532	532
Interest on lease liabilities	801	949
Total lease costs	$ 3,159	$ 3,319

Leases - Minimum Future Lease O

Leases - Minimum Future Lease Obligations (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Operating Leases
2020	$ 5,816
2021	6,506
2022	5,895
2023	4,607
2024	3,791
Thereafter	22,723
Total minimum lease payments	49,338
Less: interest	14,874
Present value of lease liabilities	34,464	$ 34,903	$ 33,564
Financing Leases
2020	7,852
2021	6,792
2022	5,178
2023	3,676
2024	2,565
Thereafter	24,080
Total minimum lease payments	50,143
Less: interest	21,765
Present value of lease liabilities	$ 28,378	$ 28,497	$ 33,363

Leases Leases - Schedule of Sal

Leases Leases - Schedule of Sale Leaseback Transactions (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Sale Leaseback Transaction [Line Items]
Financing lease assets, net	$ 35,602	$ 36,134	$ 38,263
Solar Photovoltaic Projects
Sale Leaseback Transaction [Line Items]
Financing lease assets, net	35,602	36,134
Deferred loss, short-term, net	115	115
Deferred loss, long-term, net	1,773	1,801
Total deferred loss	1,888	1,916
Financing lease liabilities, short-term	4,906	4,997
Financing lease liabilities, long-term	23,472	23,500
Total financing lease liabilities	28,378	28,497
Deferred gain, short-term, net	345	345
Deferred gain, long-term, net	5,379	5,463
Total deferred gain	$ 5,724	$ 5,808

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Thousands	1 Months Ended
	Aug. 31, 2018	Mar. 31, 2020	Dec. 31, 2019	Nov. 30, 2018
Loss Contingencies [Line Items]
Commitment for future lease payments for leases that do not yet meet the criteria of a ROU asset or liability		$ 721
Undisclosed Name of Acquiree 2
Loss Contingencies [Line Items]
Contingent consideration, liability, revenue earn-outs, payment period	5 years
Contingent consideration, liability, fair value at date of acquisition	$ 555	678	$ 678
Undisclosed Name Of Acquiree 3
Loss Contingencies [Line Items]
Contingent consideration, liability		$ 378		$ 363

Fair Value Measurement - Fair V

Fair Value Measurement - Fair Value of Assets and Liabilities Measured on a Recurring Basis (Details) - Recurring - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Liabilities:
Total liabilities	$ 12,293	$ 7,832
Level 2
Assets:
Total assets	246	213
Level 2 | Interest rate swap instruments
Assets:
Total assets	0	15
Liabilities:
Liability derivatives	10,882	6,236
Level 2 | Commodity swap instruments
Assets:
Total assets	246	198
Level 2 | Interest make-whole provisions
Liabilities:
Liability derivatives	733	918
Level 3
Liabilities:
Contingent consideration	$ 678	$ 678

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Details)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Probability of low case scenario, percentage	50.00%
Probability of base case scenario, percentage	50.00%
Fair Value, Measurements, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets, fair value disclosure, nonrecurring	$ 0	$ 0
Undisclosed Name of Acquiree 1 | Interest make-whole provisions | Measurement Input, Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.18

Fair Value Measurement - Change

Fair Value Measurement - Changes in Contingent Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Contingent consideration liabilities balance at December 31, 2019 and 2018	$ 678	$ 600
Changes in the fair value of contingent consideration obligation	0	25
Contingent consideration liabilities balance at March 31, 2020 and 2019	$ 678	$ 625

Fair Value Measurement - Fair_2

Fair Value Measurement - Fair Value and Carrying Value of Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Long-term debt value (Level 2), Fair Value	$ 332,683	$ 309,377
Long-term debt value (Level 2), Carrying Value	$ 326,459	$ 307,508

Derivative Instruments and He_3

Derivative Instruments and Hedging Activities - Fair Value of Derivative Instruments on the Balance Sheet (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Designated | Interest rate swap instruments | Other assets
Derivatives, Fair Value [Line Items]
Asset derivatives	$ 0	$ 15
Designated | Interest rate swap instruments | Other liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives	10,846	6,210
Not Designated | Interest rate swap instruments | Other liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives	36	26
Not Designated | Commodity swap contracts | Other assets
Derivatives, Fair Value [Line Items]
Asset derivatives	246	198
Not Designated | Commodity swap contracts | Other liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives	0	0
Not Designated | Interest make-whole provisions | Other liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives	$ 733	$ 918

Derivative Instruments and He_4

Derivative Instruments and Hedging Activities - Additional Information (Details) - contract	Mar. 31, 2020	Dec. 31, 2019
Not Designated
Derivative [Line Items]
Number of instruments held	3	3

Derivative Instruments and He_5

Derivative Instruments and Hedging Activities - Effects on Statements of Income (Loss) and Consolidated Statements of Comprehensive Loss (Details) - Other expenses, net - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Designated | Interest rate swap instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) Loss Recognized in Net Income	$ 99	$ (49)
Not Designated | Interest rate swap instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) Loss Recognized in Net Income	10	0
Not Designated | Commodity swap contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) Loss Recognized in Net Income	(48)	0
Not Designated | Interest make-whole provisions
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) Loss Recognized in Net Income	$ (185)	$ (723)

Derivative Instruments and He_6

Derivative Instruments and Hedging Activities - Effects of Derivative Instruments in Accumulated Other Comprehensive Loss (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Unrealized Gain (Loss) Recognized in Accumulated Other Comprehensive Loss
Beginning balance	$ 428,856
Ending balance	432,177
Accumulated Gain (Loss), Net, Cash Flow Hedge
Unrealized Gain (Loss) Recognized in Accumulated Other Comprehensive Loss
Beginning balance	(4,742)
Unrealized loss recognized in AOCI	(3,564)
Loss reclassified from AOCI to other expenses, net	99
Ending balance	$ (8,207)

Derivative Instruments and He_7

Derivative Instruments and Hedging Activities - Summary of Active Derivative Instruments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)MMBTU$ / MMBTU	Dec. 31, 2019USD ($)
Designated | Interest Rate Swap October 2029
Derivative [Line Items]
Term of contract, years	11 years
Fixed interest rate, percentage	5.77%
Initial Notional Amount ($)	$ 9,200
Designated | Interest Rate Swap June 2033
Derivative [Line Items]
Term of contract, years	15 years
Fixed interest rate, percentage	5.24%
Initial Notional Amount ($)	$ 10,000
Designated | Interest Rate Swap - December 2027
Derivative [Line Items]
Term of contract, years	10 years
Fixed interest rate, percentage	4.74%
Initial Notional Amount ($)	$ 14,100
Designated | Interest Rate Swap - December 2038
Derivative [Line Items]
Term of contract, years	15 years
Fixed interest rate, percentage	3.26%
Initial Notional Amount ($)	$ 14,084
Designated | Interest Rate Swap - February 2023
Derivative [Line Items]
Term of contract, years	7 years
Fixed interest rate, percentage	2.19%
Initial Notional Amount ($)	$ 20,746
Designated | Interest Rate Swap - June 2028
Derivative [Line Items]
Term of contract, years	8 years
Fixed interest rate, percentage	3.70%
Initial Notional Amount ($)	$ 14,643
Designated | Interest Rate Swap - June 2028
Derivative [Line Items]
Term of contract, years	8 years
Fixed interest rate, percentage	3.70%
Initial Notional Amount ($)	$ 10,734
Designated | Interest Rate Swap - February 2021
Derivative [Line Items]
Term of contract, years	15 years
Fixed interest rate, percentage	5.30%
Initial Notional Amount ($)	$ 3,256
Designated | Interest Rate Swap - March 2024
Derivative [Line Items]
Term of contract, years	15 years 6 months
Fixed interest rate, percentage	5.40%
Initial Notional Amount ($)	$ 13,081
Not Designated | Interest Rate Swap - December 2020
Derivative [Line Items]
Term of contract, years	3 years
Fixed interest rate, percentage	2.46%
Initial Notional Amount ($)	$ 17,100
Not Designated | Commodity Contract - April 2020
Derivative [Line Items]
Term of contract, years	1 year
Active Commodity Swap, price (in usd per unit) | $ / MMBTU	2.68
Nonmonetary notional amount (in MMBtus) | MMBTU	437,004
Not Designated | Commodity Contract - April 2021
Derivative [Line Items]
Term of contract, years	1 year
Active Commodity Swap, price (in usd per unit) | $ / MMBTU	2.70
Nonmonetary notional amount (in MMBtus) | MMBTU	435,810
Not Designated | Other liabilities | Interest make-whole provisions
Derivative [Line Items]
Liability derivatives, fair value	$ 733	$ 918

Investment Funds And Other Va_3

Investment Funds And Other Variable Interest Entities - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)fund	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Variable Interest Entity [Line Items]
Number of investment funds | fund	5
Net asset position of equity method joint ventures			$ 1,292
Expense recognized from equity method joint ventures	$ 53	$ 0

Investment Funds and Other Va_4

Investment Funds and Other Variable Interest Entities - Schedule of Variable Interest Entity Financial Information (Details) - USD ($) $ in Thousands		Mar. 31, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Variable interest entities, current assets	[1]	$ 438,092	$ 425,192
Total assets	[1]	1,413,583	1,374,013
Variable interest entities, current liabilities	[1]	316,079	336,647
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current assets		8,272	7,017
Total assets		163,019	158,912
Variable interest entities, current liabilities		6,633	6,563
Total VIE liabilities		38,024	38,568
Cash and cash equivalents | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current assets		5,789	4,666
Restricted cash | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current assets		586	586
Accounts receivable, net | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current assets		462	532
Costs and estimated earnings in excess of billings | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current assets		1,355	1,125
Prepaid expenses and other current assets | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current assets		80	108
Property and equipment, net | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, noncurrent assets		1,266	1,266
Energy assets, net | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, noncurrent assets		145,410	142,456
Operating lease assets | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, noncurrent assets		6,411	6,511
Other assets | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, noncurrent assets		1,660	1,662
Current portions of long-term debt and financing lease liabilities | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current liabilities		2,234	2,252
Accounts payable | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current liabilities		2,670	2,006
Accrued expenses and other current liabilities | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current liabilities		1,623	2,203
Current portions of operating lease liabilities | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, current liabilities		106	102
Long-term debt and financing lease liabilities, less current portions and net of deferred financing fees | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, noncurrent liabilities		24,214	24,654
Long-term portions of operating lease liabilities | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, noncurrent liabilities		6,173	6,180
Other liabilities | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Variable interest entities, noncurrent liabilities		$ 1,004	$ 1,171
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Non-Controlling Interests and_2

Non-Controlling Interests and Equity (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2015
Variable Interest Entity [Line Items]
Term of extension of call option		6 months	6 months	6 months	6 months	6 months
Term of extension of put option		6 months	6 months	6 months	1 year	1 year
Percentage of investor contributed capital balance, percentage	7.00%
Remaining investor contributed capital balance	5.00%
Redeemable non-controlling interests	$ 31,939,000	$ 31,616,000
Minimum
Variable Interest Entity [Line Items]
Exercise price of put options	659
Maximum
Variable Interest Entity [Line Items]
Exercise price of put options	$ 917

Earnings Per Share and Other _3

Earnings Per Share and Other Equity Related Information - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net income attributable to common shareholders	$ 6,201	$ 4,147
Basic weighted-average shares outstanding (in shares)	47,384	46,293
Effect of dilutive securities:
Stock options (in shares)	1,113	1,361
Diluted weighted-average shares outstanding (in shares)	48,497	47,654

Earnings Per Share and Other _4

Earnings Per Share and Other Equity Related Information - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Aug. 31, 2019	Feb. 28, 2017	Apr. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options excluded from calculation of dilutive shares as the effect would be anti-dilutive (in shares)	431,000	293,000
Stock-based compensation expense	$ 429,000	$ 385,000
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Non-vested stock options unrecognized compensation expense	$ 10,757,000
Non-vested stock options unrecognized compensation expense, weighted-average period of recognition	3 years
Options granted in period (in shares)	196
Stock options, contractual period	10 years
Stock options, vesting period	5 years
Common Class A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock repurchase program, authorized amount (up to)			$ 17,553,000	$ 15,000,000	$ 10,000,000
Treasury Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Open market purchase of common shares (in shares)	455	0

Business Segment Information (D

Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 212,413	$ 150,112
Interest income	90	133
Interest expense	3,459	2,808
Depreciation and amortization of intangible assets	9,834	8,838
Income (loss) before taxes, excluding unallocated corporate activity	14,477	11,136
U.S. Regions
Segment Reporting Information [Line Items]
Revenues	84,727	55,597
U.S. Federal
Segment Reporting Information [Line Items]
Revenues	68,745	43,057
Canada
Segment Reporting Information [Line Items]
Revenues	11,392	7,148
Non-Solar DG
Segment Reporting Information [Line Items]
Revenues	22,724	21,230
All Other
Segment Reporting Information [Line Items]
Revenues	24,825	23,080
Operating Segments | U.S. Regions
Segment Reporting Information [Line Items]
Revenues	84,727	55,597
Interest income	36	63
Interest expense	1,481	857
Depreciation and amortization of intangible assets	2,763	2,182
Income (loss) before taxes, excluding unallocated corporate activity	3,723	(278)
Operating Segments | U.S. Federal
Segment Reporting Information [Line Items]
Revenues	68,745	43,057
Interest income	40	49
Interest expense	746	210
Depreciation and amortization of intangible assets	1,017	817
Income (loss) before taxes, excluding unallocated corporate activity	7,094	5,621
Operating Segments | Canada
Segment Reporting Information [Line Items]
Revenues	11,392	7,148
Interest income	0	0
Interest expense	172	164
Depreciation and amortization of intangible assets	391	275
Income (loss) before taxes, excluding unallocated corporate activity	(221)	(289)
Operating Segments | Non-Solar DG
Segment Reporting Information [Line Items]
Revenues	22,724	21,230
Interest income	14	21
Interest expense	1,045	1,577
Depreciation and amortization of intangible assets	5,287	5,216
Income (loss) before taxes, excluding unallocated corporate activity	1,669	1,381
Operating Segments | All Other
Segment Reporting Information [Line Items]
Revenues	24,825	23,080
Interest income	0	0
Interest expense	15	0
Depreciation and amortization of intangible assets	376	348
Income (loss) before taxes, excluding unallocated corporate activity	2,212	4,701
Unallocated corporate activity
Segment Reporting Information [Line Items]
Unallocated corporate activity	$ (10,346)	$ (8,008)

Debt - Summary of Long-term Deb

Debt - Summary of Long-term Debt (Details) - USD ($) $ in Thousands		Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Debt Instrument [Line Items]
Financing leases		$ 28,378	$ 28,497	$ 33,363
Debt and financing leases, gross		361,441	343,093
Less - current maturities		69,282	69,969
Less - deferred financing fees		6,606	6,943
Long term debt and financing lease liabilities	[1]	285,553	266,181
Future interest payments		$ 21,765
Term Loan | Variable Rate Term Loan due February 2021
Debt Instrument [Line Items]
Weighted average interest rate, percentage		3.70%
Long-term debt, gross		$ 625	625
Term Loan | Variable Rate Term Loan due June 2024
Debt Instrument [Line Items]
Weighted average interest rate, percentage		3.45%
Long-term debt, gross		$ 6,609	6,609
Term Loan | Term Loan Due March 2021
Debt Instrument [Line Items]
Fixed interest rate, percentage		7.25%
Long-term debt, gross		$ 666	831
Term Loan | Term Loan Payable due June 2028
Debt Instrument [Line Items]
Fixed interest rate, percentage		6.11%
Long-term debt, gross		$ 3,314	3,649
Term Loan | Variable Rate Term Loan Due In May 2020
Debt Instrument [Line Items]
Weighted average interest rate, percentage		4.95%
Long-term debt, gross		$ 27,617	28,217
Term Loan | Variable Rate Term Loan Due In March 2023
Debt Instrument [Line Items]
Weighted average interest rate, percentage		4.20%
Long-term debt, gross		$ 15,995	15,976
Term Loan | Term Loan Due In July 2031
Debt Instrument [Line Items]
Fixed interest rate, percentage		4.95%
Long-term debt, gross		$ 3,392	3,769
Term Loan | Term Loan Due in March 2028
Debt Instrument [Line Items]
Fixed interest rate, percentage		5.00%
Long-term debt, gross		$ 3,416	3,521
Term Loan | Term Loan Due April 2027
Debt Instrument [Line Items]
Fixed interest rate, percentage		4.50%
Long-term debt, gross		$ 21,823	22,553
Term Loan | Term Loan due February 2034
Debt Instrument [Line Items]
Fixed interest rate, percentage		5.61%
Long-term debt, gross		$ 2,487	2,706
Term Loan | Variable Rate Term Loan due December 2027
Debt Instrument [Line Items]
Weighted average interest rate, percentage		3.90%
Long-term debt, gross		$ 11,740	11,740
Term Loan | Variable Rate Term Loan due in August 2022
Debt Instrument [Line Items]
Weighted average interest rate, percentage		8.95%
Long-term debt, gross		$ 12,436	15,645
Term Loan | Term Loan due December 2038
Debt Instrument [Line Items]
Fixed interest rate, percentage		5.15%
Long-term debt, gross		$ 28,073	28,583
Term Loan | Variable Rate Term Loan Due June 2033
Debt Instrument [Line Items]
Weighted average interest rate, percentage		3.50%
Long-term debt, gross		$ 9,003	9,003
Term Loan | Variable Rate Term Loan Due October 2029
Debt Instrument [Line Items]
Weighted average interest rate, percentage		3.94%
Long-term debt, gross		$ 8,923	9,092
Term Loan | Term Loan Due December 2021
Debt Instrument [Line Items]
Fixed interest rate, percentage		6.50%
Long-term debt, gross		$ 24,167	27,226
Long Term Finance Lease Liability | Long Term Finance Liability Due July 2039
Debt Instrument [Line Items]
Weighted average interest rate, percentage		0.28%
Long-term debt, gross		$ 3,785	3,841
Long Term Finance Lease Liability | Long Term Finance Liability November 2039
Debt Instrument [Line Items]
Weighted average interest rate, percentage		0.00%
Long-term debt, gross		$ 6,970	8,794
Revolving Senior Secured Credit Facility
Debt Instrument [Line Items]
Weighted average interest rate, percentage		4.36%
Long-term debt, gross		$ 142,022	$ 112,216
[1]	Includes restricted assets of consolidated variable interest entities (“VIEs”) at March 31, 2020 and December 31, 2019 of $163,019 and $158,912, respectively. Includes non-recourse liabilities of consolidated VIEs at March 31, 2020 and December 31, 2019 of $38,024 and $38,568, respectively. See Note 12.

Debt - Additional Information (

Debt - Additional Information (Details) - Line of Credit - Revolving Credit Facility $ in Thousands	Feb. 29, 2020	Mar. 31, 2020USD ($)	Mar. 01, 2020USD ($)
Debt Instrument [Line Items]
Total Funded Debt to EBITDA covenant ratio, maximum	3.25		3.75
Long-term debt			$ 185,000
Funds available for borrowing		$ 20,736
Eurocurrency Rate
Debt Instrument [Line Items]
Debt instrument, Eurocurrency Rate floor	0.00%	1.00%

Uncategorized Items - amrc-2020

Label	Element	Value
AOCI Attributable to Parent [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (217,000)