Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2018	Aug. 01, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2
Trading Symbol	VSLR
Entity Registrant Name	Vivint Solar, Inc.
Entity Central Index Key	0001607716
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		118,599,228

Condensed Consolidated Balance Sheets (Unaudited) - USD ($)
$ in Thousands

Jun. 30, 2018

Dec. 31, 2017

Current assets:

Cash and cash equivalents

$ 174,006

$ 108,452

Accounts receivable, net

24,354

19,665

Inventories

13,135

22,597

Prepaid expenses and other current assets

25,620

34,049

Total current assets

237,115

184,763

Restricted cash and cash equivalents

66,694

46,486

Solar energy systems, net

1,784,800

1,673,532

Property and equipment, net

12,018

15,078

Intangible assets, net

595

862

Prepaid tax asset, net

505,883

Other non-current assets, net

28,064

37,325

TOTAL ASSETS

^[1]

2,129,286

2,463,929

Current liabilities:

Accounts payable

44,435

40,736

Accounts payable—related party

73

163

Distributions payable to non-controlling interests and redeemable non-controlling interests

10,114

16,437

Accrued compensation

18,015

20,992

Current portion of long-term debt

10,018

13,585

Current portion of deferred revenue

22,108

41,846

Current portion of capital lease obligation

2,758

4,166

Accrued and other current liabilities

26,090

29,675

Total current liabilities

133,611

167,600

Long-term debt, net of current portion

1,110,044

925,964

Deferred revenue, net of current portion

12,027

29,200

Capital lease obligation, net of current portion

957

1,599

Deferred tax liability, net

385,907

342,382

Other non-current liabilities

16,870

13,674

Total liabilities

^[1]

1,659,416

1,480,419

Commitments and contingencies (Note 17)

Redeemable non-controlling interests

122,647

122,444

Stockholders’ equity:

Common stock, $0.01 par value—1,000,000 authorized, 118,477 shares issued and outstanding as of June 30, 2018; 1,000,000 authorized, 115,099 shares issued and outstanding as of December 31, 2017

1,185

1,151

Additional paid-in capital

567,372

559,788

Accumulated other comprehensive (loss) income

(3,185)

6,905

(Accumulated deficit) retained earnings

(258,899)

213,107

Total stockholders’ equity

306,473

780,951

Non-controlling interests

40,750

80,115

Total equity

347,223

861,066

TOTAL LIABILITIES, REDEEMABLE NON-CONTROLLING INTERESTS AND EQUITY

$ 2,129,286

$ 2,463,929

[1]

The Company’s assets as of June 30, 2018 and December 31, 2017 include $1,630.2 million and $1,516.2 million consisting of assets of variable interest entities, or VIEs, that can only be used to settle obligations of the VIEs. These assets include solar energy systems, net, of $1,577.1 million and $1,486.0 million as of June 30, 2018 and December 31, 2017; cash and cash equivalents of $29.2 million and $17.3 million as of June 30, 2018 and December 31, 2017; accounts receivable, net, of $14.4 million and $5.1 million as of June 30, 2018 and December 31, 2017; other non-current assets, net of $8.3 million and $6.8 million as of June 30, 2018 and December 31, 2017; and prepaid expenses and other current assets of $1.2 million and $1.0 million as of June 30, 2018 and December 31, 2017. The Company’s liabilities as of June 30, 2018 and December 31, 2017 included $26.5 million and $58.4 million of liabilities of VIEs whose creditors have no recourse to the Company. These liabilities include distributions payable to non-controlling interests and redeemable non-controlling interests of $10.1 million and $16.4 million as of June 30, 2018 and December 31, 2017; deferred revenue of $10.8 million and $36.0 million as of June 30, 2018 and December 31, 2017; accrued and other current liabilities of $4.5 million as of June 30, 2018 and December 31, 2017; and other non-current liabilities of $1.1 million and $1.4 million as of June 30, 2018 and December 31, 2017. For further information see Note 12—Investment Funds.

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)
$ in Thousands

Jun. 30, 2018

Dec. 31, 2017

Common stock, par value

$ 0.01

Common stock, shares authorized

1,000,000,000

Common stock, shares issued

118,477,000

115,099,000

Common stock, shares outstanding

118,477,000

115,099,000

Total assets

^[1]

$ 2,129,286

$ 2,463,929

Solar energy systems, net

1,784,800

1,673,532

Cash and cash equivalents

174,006

108,452

Accounts receivable, net

24,354

19,665

Other non-current assets, net

28,064

37,325

Prepaid expenses and other current assets

25,620

34,049

Total liabilities

^[1]

1,659,416

1,480,419

Distributions payable to non-controlling interests and redeemable non-controlling interests

10,114

16,437

Accrued and other current liabilities

26,090

29,675

Other non-current liabilities

16,870

13,674

Variable Interest Entities

Total assets

1,630,217

1,516,190

Solar energy systems, net

1,577,144

1,486,023

Cash and cash equivalents

29,182

17,280

Accounts receivable, net

14,419

5,143

Other non-current assets, net

8,317

6,792

Prepaid expenses and other current assets

1,155

952

Total liabilities

26,498

58,382

Distributions payable to non-controlling interests and redeemable non-controlling interests

10,114

16,437

Deferred revenue

10,800

36,000

Accrued and other current liabilities

4,465

4,478

Other non-current liabilities

$ 1,125

$ 1,444

[1]

The Company’s assets as of June 30, 2018 and December 31, 2017 include $1,630.2 million and $1,516.2 million consisting of assets of variable interest entities, or VIEs, that can only be used to settle obligations of the VIEs. These assets include solar energy systems, net, of $1,577.1 million and $1,486.0 million as of June 30, 2018 and December 31, 2017; cash and cash equivalents of $29.2 million and $17.3 million as of June 30, 2018 and December 31, 2017; accounts receivable, net, of $14.4 million and $5.1 million as of June 30, 2018 and December 31, 2017; other non-current assets, net of $8.3 million and $6.8 million as of June 30, 2018 and December 31, 2017; and prepaid expenses and other current assets of $1.2 million and $1.0 million as of June 30, 2018 and December 31, 2017. The Company’s liabilities as of June 30, 2018 and December 31, 2017 included $26.5 million and $58.4 million of liabilities of VIEs whose creditors have no recourse to the Company. These liabilities include distributions payable to non-controlling interests and redeemable non-controlling interests of $10.1 million and $16.4 million as of June 30, 2018 and December 31, 2017; deferred revenue of $10.8 million and $36.0 million as of June 30, 2018 and December 31, 2017; accrued and other current liabilities of $4.5 million as of June 30, 2018 and December 31, 2017; and other non-current liabilities of $1.1 million and $1.4 million as of June 30, 2018 and December 31, 2017. For further information see Note 12—Investment Funds.

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue:
Operating leases and incentives	$ 54,765	$ 43,413	$ 85,879	$ 73,802
Solar energy system and product sales	26,033	29,582	63,169	52,307
Total revenue	80,798	72,995	149,048	126,109
Cost of revenue:
Cost of revenue—operating leases and incentives	41,366	33,763	80,053	68,833
Cost of revenue—solar energy system and product sales	18,990	22,831	45,035	41,496
Total cost of revenue	60,356	56,594	125,088	110,329
Gross profit	20,442	16,401	23,960	15,780
Operating expenses:
Sales and marketing	14,033	9,411	25,158	18,229
Research and development	511	895	997	1,791
General and administrative	21,879	20,301	41,730	40,880
Amortization of intangible assets	130	139	266	279
Total operating expenses	36,553	30,746	68,151	61,179
Loss from operations	(16,111)	(14,345)	(44,191)	(45,399)
Interest expense	11,336	16,838	28,258	31,559
Other (income) expense, net	(4,109)	715	(6,370)	991
Loss before income taxes	(23,338)	(31,898)	(66,079)	(77,949)
Income tax expense	35,352	5,156	53,995	14,557
Net loss	(58,690)	(37,054)	(120,074)	(92,506)
Net loss attributable to non-controlling interests and redeemable non-controlling interests	(76,806)	(42,034)	(125,214)	(110,778)
Net income available to common stockholders	$ 18,116	$ 4,980	$ 5,140	$ 18,272
Net income available per share to common stockholders:
Basic	$ 0.16	$ 0.04	$ 0.04	$ 0.16
Diluted	$ 0.15	$ 0.04	$ 0.04	$ 0.16
Weighted-average shares used in computing net income available per share to common stockholders:
Basic	116,650	112,351	115,907	111,562
Diluted	121,753	117,570	120,969	116,988

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income available to common stockholders	$ 18,116	$ 4,980	$ 5,140	$ 18,272
Other comprehensive loss:
Unrealized (losses) gains on cash flow hedging instruments (net of tax effect of $(223), $(727), $1,171 and $(745))	(602)	(1,087)	3,147	(1,115)
Less: Interest income (expense) on derivatives recognized into earnings (net of tax effect of $6,058, $3, $6,161 and $(57))	16,277	4	16,555	(86)
Total other comprehensive loss	(16,879)	(1,083)	(13,408)	(1,201)
Comprehensive income (loss)	$ 1,237	$ 3,897	$ (8,268)	$ 17,071

Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Unrealized losses on cash flow hedging instruments, tax	$ (223)	$ (727)	$ 1,171	$ (745)
Interest expense on derivatives recognized into earnings, tax	$ 6,058	$ 3	$ 6,161	$ (57)

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (120,074)	$ (92,506)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	33,174	29,039
Amortization of intangible assets	266	279
Deferred income taxes	54,173	65,255
Stock-based compensation	6,781	7,252
Loss on solar energy systems and property and equipment	3,025	3,766
Non-cash interest and other expense	13,656	5,311
Reduction in lease pass-through financing obligation	(2,164)	(1,995)
(Gains) losses on interest rate swaps	(1,279)	993
Changes in operating assets and liabilities:
Accounts receivable, net	(4,689)	(9,015)
Inventories	9,462	(4,856)
Prepaid expenses and other current assets	8,276	21,373
Prepaid tax asset, net		(43,106)
Other non-current assets, net	(6,613)	(6,025)
Accounts payable	1,898	(115)
Accrued compensation	(2,329)	(2,022)
Deferred revenue	(10,514)	6,669
Accrued and other liabilities	(1,915)	6,279
Net cash used in operating activities	(18,866)	(13,424)
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments for the cost of solar energy systems	(146,247)	(145,033)
Payments for property and equipment	(65)	(633)
Proceeds from disposals of solar energy systems and property and equipment	1,843	1,100
Net cash used in investing activities	(144,469)	(144,566)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from investment by non-controlling interests and redeemable non-controlling interests	108,287	115,514
Distributions paid to non-controlling interests and redeemable non-controlling interests	(28,558)	(22,480)
Proceeds from long-term debt	876,000	273,750
Payments on long-term debt	(689,320)	(159,304)
Payments for debt issuance and deferred offering costs	(17,715)	(13,410)
Proceeds from lease pass-through financing obligation	1,497	1,487
Principal payments on capital lease obligations	(1,931)	(2,343)
Proceeds from issuance of common stock	837	233
Net cash provided by financing activities	249,097	193,447
NET INCREASE IN CASH AND CASH EQUIVALENTS, INCLUDING RESTRICTED AMOUNTS	85,762	35,457
CASH AND CASH EQUIVALENTS, INCLUDING RESTRICTED AMOUNTS—Beginning of period	154,938	123,439
CASH AND CASH EQUIVALENTS, INCLUDING RESTRICTED AMOUNTS—End of period	240,700	158,896
NONCASH INVESTING AND FINANCING ACTIVITIES:
Accrued distributions to non-controlling interests and redeemable non-controlling interests	(6,323)	(6,721)
Costs of solar energy systems included in changes in accounts payable, accounts payable—related party, accrued compensation and accrued and other liabilities	(119)	(6,335)
Vehicles acquired under capital leases	619	369
Solar energy system sales
NONCASH INVESTING AND FINANCING ACTIVITIES:
Receivable for state tax credits recorded as a reduction to solar energy system costs	$ 9	$ 87

Organization

6 Months Ended

Jun. 30, 2018

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Organization

1.	Organization

Vivint Solar, Inc. and its subsidiaries are collectively referred to as the “Company.” The Company most commonly offers solar energy to residential customers through long-term customer contracts, such as power purchase agreements (“PPAs”) and legal-form leases (“Solar Leases”). The Company also offers its customers the option to purchase solar energy systems (“System Sales”) through third-party loan offerings or a cash purchase. The Company enters into customer contracts through a sales organization that primarily uses a direct-to-home sales model. The long-term customer contracts under PPAs and Solar Leases are typically for 20 years and require the customer to make monthly payments to the Company.

The Company has formed various investment funds and entered into long-term debt facilities to monetize the recurring customer payments under its long-term customer contracts and the investment tax credits, accelerated tax depreciation and other incentives associated with residential solar energy systems. The Company uses the cash received from the investment funds, long-term debt facilities and cash generated from operations, including System Sales, to finance a portion of the Company’s variable and fixed costs associated with installing solar energy systems.

Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2018

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2.	Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and applicable rules and regulations of the Securities and Exchange Commission regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. As such, these unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and accompanying notes included in the Company’s annual report on Form 10-K dated as of March 7, 2018. The unaudited condensed consolidated financial statements were prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, reflect all adjustments (all of which were considered of normal recurring nature) considered necessary to present fairly the Company’s financial results. The results of the six months ended June 30, 2018 are not necessarily indicative of the results to be expected for the fiscal year ending December 31, 2018 or for any other interim period or other future year.

The unaudited condensed consolidated financial statements reflect the accounts and operations of the Company and those of its subsidiaries in which the Company has a controlling financial interest. The Company uses a qualitative approach in assessing the consolidation requirement for variable interest entities (“VIEs”). This approach 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. All of these determinations involve significant management judgments and estimates. The Company has determined that it is the primary beneficiary in the operational VIEs in which it has an equity interest. The Company evaluates its relationships with the VIEs on an ongoing basis to ensure that it continues to be the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation. For additional information, see Note 12—Investment Funds.

Certain prior period amounts have been reclassified to conform to current year presentation. These reclassifications did not have a significant impact on the consolidated financial statements.

Use of Estimates

The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. The Company regularly makes significant estimates and assumptions including, but not limited to, investment tax credits (“ITCs”); revenue recognition; solar energy systems, net; the impairment analysis of long-lived assets; stock-based compensation; the provision for income taxes; the valuation of derivative financial instruments; the recognition and measurement of loss contingencies; and non-controlling interests and redeemable non-controlling interests. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could differ materially from those estimates.

Liquidity

In order to grow, the Company requires cash to finance the deployment of solar energy systems. As of the date of this filing, the Company will require additional sources of cash beyond current cash balances, and currently available financing facilities to fund long-term planned growth. If the Company is unable to secure additional financing when needed, or upon desirable terms, the Company may be unable to finance installation of customers’ systems in a manner consistent with past performance, cost of capital could increase, or the Company may be required to significantly reduce the scope of operations, any of which would have a material adverse effect on its business, financial condition, results of operations and prospects. While the Company believes additional financing is available and will continue to be available to support current levels of operations, the Company believes it has the ability and intent to reduce operations to the level of available financial resources for at least the next 12 months from the date of this report, if necessary.

Revenue from Contracts with Customers

The Company adopted ASU 2014-09, Revenue from Contracts with Customers, and its various updates (“Topic 606”) effective January 1, 2018 using the modified retrospective method with a cumulative adjustment to retained earnings as of January 1, 2018. As such, only the current period presented in the Company’s condensed consolidated statements of operations has been reported using the new revenue standard. The Company has applied Topic 606 to all customer contracts not completed by the initial date of application.

The Company currently accounts for PPAs, Solar Leases, and associated rebates and incentives as minimum lease payments from operating leases under ASC 840, Leases. However, the Company has determined that these agreements do not meet the definition of a lease under ASC 842, Leases, and these agreements will be accounted for in accordance with Topic 606 after the adoption of ASC 842. The revenue associated with these contracts with customers is currently shown together on the condensed consolidated statement of operations as revenue from operating leases and incentives. The Company will adopt ASC 842 effective January 1, 2019. The Company has determined that under Topic 606 there will be no change from current revenue recognition practices for its PPA revenue stream. For the Company’s Solar Leases, the Company has concluded that the impact of adopting Topic 606 will be immaterial. Revenue from all of the Company’s Solar Leases will be recognized on a straight-line basis over the contractual term; currently a significant majority of Solar Leases are already recognized on a straight-line basis. The Company has also concluded that there will be no material change related to the timing of revenue recognition for rebates and incentives.

The Company has analyzed the impact of Topic 606 on System Sales and other product sales and has concluded that the revenue recognition associated with these product sales did not change in the condensed consolidated financial statements. The Company will continue to show this revenue stream as solar energy system and product sales in the condensed consolidated statement of operations. The Company’s principal performance obligation for System Sales is to design and install a solar energy system that is interconnected to the local power grid and granted permission to operate to the customer. When the solar energy system has been granted permission to operate, the customer retains all of the significant risks and rewards of ownership of the solar energy system. For certain System Sales, the Company provides limited post-sale services to monitor the productivity of the solar energy system for 20 years after it has been placed in service. The Company collects cash during the installation process and recognizes revenue for System Sales and other product sales at the placed in-service date or product delivery date less any revenue allocated to monitoring services. The Company allocates a portion of the transaction price to the monitoring services by estimating the fair market price that the Company would charge for these services if offered separately from the sale of the solar energy system. As of June 30, 2018 and December 31, 2017, the Company had allocated deferred revenue of $2.7 million and $2.1 million to monitoring services that will be recognized over the term of the monitoring services. All costs to obtain and fulfill contracts associated with System Sales and other product sales are expensed as a cost of revenue when the Company has fulfilled its performance obligation and the products have been placed into service or delivered to the customer.

The Company has assessed the impact of Topic 606 as it relates to the sales of ITCs through its lease pass-through fund arrangement. The Company has concluded that revenue related to the sale of ITCs through its lease pass-through arrangement is recognized when the related solar energy systems are placed in service as the Company has completed its performance obligation to transfer ITCs to the fund investors at that time. The fund investors contributed cash to the investment fund during the installation process as payment for the ITCs. The transaction price for the ITCs was estimated using the tax credit rate of 30% multiplied by the fair market value of the solar energy systems that were placed into service in the lease pass-through fund. All of the related solar energy systems were placed in service and all related revenue would have been recognized prior to September 30, 2016 under Topic 606. Prior to the adoption of Topic 606, the Company recognized this revenue evenly over the five-year ITC recapture period. This earlier recognition of the ITC lease pass-through revenue decreased revenue for the three and six months ended June 30, 2018 by $0.9 million and $3.2 million and would have decreased revenue for the three and six months ended June 30, 2017 by $0.9 million and $3.2 million. As all ITC sales revenue would have been recognized prior to September 30, 2016 under Topic 606, there is no deferred revenue related to ITC sales recorded after the adoption date of January 1, 2018, and there would have been no deferred revenue as of December 31, 2017. As shown below, the cumulative adjustment related to ITC revenue recognized into retained earnings, net of tax, as of January 1, 2018 was $19.2 million.

As noted above, the Company adopted Topic 606 on a modified retrospective basis. However, if the Company adjusted the comparative period to reflect the adoption of Topic 606, the following adjustments would have been made to the condensed consolidated statement of operations for the three and six months ended June 30, 2017 (in thousands, except per share data):

	Three Months Ended June 30, 2017							Six Months Ended June 30, 2017
	As Previously		Revenue					As Previously		Revenue
	Reported		Adjustment			As Adjusted		Reported		Adjustment			As Adjusted
Revenue	$	72,995	$	(865	)	$	72,130	$	126,109	$	(3,229	)	$	122,880
Income tax expense		5,156		(234	)		4,922		14,557		(875	)		13,682
Net income available to common shareholders		4,980		(631	)		4,349		18,272		(2,354	)		15,918
Diluted earnings per share		0.04		(0.01	)		0.03		0.16		(0.02	)		0.14

Additionally, the following adjustments would have been made to the condensed consolidated balance sheet as of December 31, 2017 (in thousands):

	As Previously		Revenue
	Reported		Adjustment			As Adjusted
Current portion of deferred revenue	$	41,846	$	(7,707	)	$	34,139
Deferred revenue, net of current portion		29,200		(18,690	)		10,510
Deferred tax liability, net		342,382		7,160			349,542

Retained earnings		213,107		(19,237	)		193,870

Income Taxes

The Company adopted ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory (“ASU 2016-16”), effective January 1, 2018 using the modified retrospective method by removing the prepaid tax asset, net and recording a cumulative adjustment to retained earnings of $493.1 million and to deferred tax liability, net of $12.8 million as of January 1, 2018. As such, only the current periods presented in the Company’s condensed consolidated statements of operations have been reported using the new accounting standard. The Company now accounts for the income tax consequences of these intra-entity transfers, both current and deferred, as a component of income tax expense and deferred tax liability, net during the period in which the transfers occur.

The adoption of ASU 2016-16 had the following effect on the Company’s condensed consolidated statement of operations for the three and six months ended June 30, 2018 (in thousands, except per share data):

	Three Months Ended June 30, 2018									Six Months Ended June 30, 2018
	Pre-Adoption			Effect of						Pre-Adoption			Effect of
	Accounting			Adoption			As Reported			Accounting			Adoption			As Reported
Income tax expense	$	18,598		$	16,754		$	35,352		$	24,379		$	29,616		$	53,995
Net loss		(41,936	)		(16,754	)		(58,690	)		(90,458	)		(29,616	)		(120,074	)
Net loss attributable to common shareholders		34,870			(16,754	)		18,116			34,756			(29,616	)		5,140
Basic earnings per share		0.30			(0.14	)		0.16			0.30			(0.26	)		0.04
Diluted earnings per share		0.29			(0.14	)		0.15			0.29			(0.25	)		0.04

The Company adopted ASU 2018-02, Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (“ASU 2018-02”), effective January 1, 2018. As permitted by ASU 2018-02, the Company has elected to reclassify the income tax effects of the Tax Cuts and Jobs Act (the “TCJA”) on items within accumulated other comprehensive income (“AOCI”) to retained earnings. The Company applied the amendments in this update in the period of adoption. The total amount the Company reclassified to retained earnings as a result of adopting ASU 2018-02 was approximately $1.5 million. After applying this update, the Company had no stranded tax effects remaining in AOCI.

Derivative Financial Instruments

The Company adopted ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities (“ASU 2017-12”), effective January 1, 2018. This update made targeted improvements to accounting for hedging activities by simplifying certain documentation and assessment requirements and eliminating the requirement to separately measure and report hedge ineffectiveness. The Company applied this update using a modified retrospective method to eliminate the separate measurement of hedge ineffectiveness by recording a cumulative-effect adjustment to retained earnings as of January 1, 2018. The net amount the Company recorded to retained earnings as a result of adopting ASU 2017-12 was approximately $1.8 million.

Restricted Cash

The Company adopted ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force) (“ASU 2016-18”), effective January 1, 2018. This update clarified that transfers between cash and restricted cash are not reported as cash flow activities in the statements of cash flows. As such, restricted cash amounts are included with cash and cash equivalents in the beginning-of-period and end-of-period total amounts on the statements of cash flows. The Company applied this update retrospectively, which resulted in an adjustment to the beginning-of-period and end-of-period total amounts on the condensed consolidated statement of cash flows for the six months ended June 30, 2017 to include restricted cash balances from those periods.

Recent Accounting Pronouncements

In July 2018, the Financial Accounting Standards Board (the “FASB”) issued ASU 2018-10 and ASU 2018-11, which clarify aspects of the guidance in ASU 2016-02, Leases (Topic 842). The objective of ASU 2016-02 is to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. This update primarily changes the recognition by lessees of lease assets and liabilities for leases currently classified as operating leases. Lessor accounting remains largely unchanged. This update is effective in fiscal years beginning after December 15, 2018 for public business entities and early adoption is permitted. The amendments are required to be applied using a modified retrospective approach. However, ASU 2018-11 provides an additional transition method under which an entity will apply the updates in ASU 2016-02 as of the adoption date with a cumulative-effect adjustment to the opening balance of retained earnings. Under this additional transition method, periods ending prior to January 1, 2019 will be presented in accordance with ASC 840, and periods ending after January 1, 2019 will be presented in accordance with ASC 842. The Company will adopt this standard effective January 1, 2019 and plans to utilize the transition method permitted by ASU 2018-11. The Company has operating leases that will be affected by this update and the Company is still evaluating the full impact on its condensed consolidated financial statements and related disclosures. The impact is not expected to be significant to the Company’s condensed consolidated financial statements.

In June 2018, the FASB issued ASU 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. This update expands the scope of Topic 718 to include share-based payments to nonemployees. Under current guidance, the measurement date for nonemployee equity awards is not established until the nonemployee’s performance is complete. This update states that the measurement date for nonemployee equity awards will now be established at the grant date. This amendment is effective for annual periods beginning after December 15, 2018 and is applied through a modified retrospective method with a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year of adoption. The Company has outstanding nonemployee equity awards that will be affected by this update. The impact to the Company will not be known until the date of adoption, as it will depend on the Company’s stock price on the adoption date. However, the Company currently marks all nonemployee awards to market at each reporting period and as such, the impact is not expected to be significant.

Fair Value Measurements

6 Months Ended

Jun. 30, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

3.	Fair Value Measurements

The Company measures and reports its cash equivalents at fair value. The following tables set forth the fair value of the Company’s financial assets and liabilities measured on a recurring basis by level within the fair value hierarchy (in thousands):

	June 30, 2018
	Level 1		Level 2		Level 3		Total
Financial Liabilities
Interest rate swaps	$	—	$	4,370	$	—	$	4,370

	December 31, 2017
	Level 1		Level 2		Level 3		Total
Financial Assets
Interest rate swaps	$	—	$	14,028	$	—	$	14,028

Financial Liabilities
Interest rate swaps	$	—	$	1,280	$	—	$	1,280

The interest rate swaps (Level 2) were valued using a discounted cash flow model which incorporates an assessment of the risk of non-performance by the interest rate swap counterparties and the Company. The valuation model uses various observable inputs including contractual terms, interest rate curves, credit spreads and measures of volatility. During the six months ended June 30, 2018, the Company settled the interest rate swaps associated with its 2016 Term Loan Facility and Aggregation Facility. The settlement of the interest rate swaps on the 2016 Term Loan Facility, which were designated as hedges, resulted in a $22.5 million realized gain that was recorded as a reduction to interest expense. The settlement of the interest rate swaps on the Aggregation Facility, which were not designated as hedges, resulted in a $2.0 million realized gain that was recorded as other income.

The carrying values and fair values of the Company’s long-term debt were as follows (in thousands):

	June 30, 2018				December 31, 2017
	Carrying Value		Fair Value		Carrying Value		Fair Value
Floating-rate long-term debt	$	481,500	$	481,500	$	757,044	$	757,044
Fixed-rate long-term debt		661,286		684,532		199,063		238,618
Total	$	1,142,786	$	1,166,032	$	956,107	$	995,662

The Company’s outstanding principal balance of long-term debt is carried at cost. The Company estimated the fair values of its floating-rate debt facilities to approximate their carrying values as interest accrues at floating rates based on market rates. The Company’s fixed-rate debt facilities (Level 2) were valued using quoted prices for corporate debt with similar terms.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Inventories

6 Months Ended

Jun. 30, 2018

Inventory Disclosure [Abstract]

Inventories

4.	Inventories

Inventories consisted of the following (in thousands):

	June 30,		December 31,
	2018		2017
Solar energy systems held for sale	$	12,113	$	21,971
Photovoltaic installation products		1,022		626
Total inventories	$	13,135	$	22,597

Solar energy systems held for sale are solar energy systems under construction that have yet to be interconnected to the power grid and that will be sold to customers. Solar energy systems held for sale are stated at the lower of cost, on a first-in, first-out basis, or net realizable value. Photovoltaic installation products are stated at the lower of cost, on an average cost basis, or net realizable value.

Solar Energy Systems

6 Months Ended

Jun. 30, 2018

Solar Energy Systems Disclosure [Abstract]

Solar Energy Systems

5.	Solar Energy Systems

Solar energy systems, net consisted of the following (in thousands):

	June 30,			December 31,
	2018			2017
System equipment costs	$	1,540,791		$	1,437,419
Initial direct costs related to solar energy systems		375,759			336,136
		1,916,550			1,773,555
Less: Accumulated depreciation and amortization		(161,124	)		(129,640	)
		1,755,426			1,643,915
Solar energy system inventory		29,374			29,617
Solar energy systems, net	$	1,784,800		$	1,673,532

Solar energy system inventory represents the solar components and materials used in the installation of solar energy systems prior to being installed on customers’ roofs. As such, no depreciation is recorded related to this line item. The Company recorded depreciation and amortization expense related to solar energy systems of $16.1 million and $13.7 million for the three months ended June 30, 2018 and 2017. The Company recorded depreciation and amortization expense related to solar energy systems of $31.5 million and $26.5 million for the six months ended June 30, 2018 and 2017.

Property and Equipment

6 Months Ended

Jun. 30, 2018

Property Plant And Equipment [Abstract]

Property and Equipment

6.	Property and Equipment

Property and equipment, net consisted of the following (in thousands):

	Estimated	June 30,			December 31,
	Useful Lives	2018			2017
Vehicles acquired under capital leases	3-5 years	$	11,403		$	15,113
Leasehold improvements	1-12 years		12,301			15,071
Furniture and computer and other equipment	3 years		4,115			6,492
			27,819			36,676
Less: Accumulated depreciation and amortization			(15,801	)		(21,598	)
Property and equipment, net		$	12,018		$	15,078

The Company recorded depreciation and amortization expense related to property and equipment of $1.3 million and $2.1 million for the three months ended June 30, 2018 and 2017. The Company recorded depreciation and amortization expense related to property and equipment of $3.0 million and $4.5 million for the six months ended June 30, 2018 and 2017.

The Company leases fleet vehicles that are accounted for as capital leases and are included in property and equipment, net. Of total property and equipment depreciation and amortization, depreciation on vehicles under capital leases of $0.6 million and $0.9 million was capitalized in solar energy systems, net for the three months ended June 30, 2018 and 2017. The Company capitalized depreciation on vehicles under capital leases of $1.3 million and $2.0 million in solar energy systems, net for the six months ended June 30, 2018 and 2017.

Intangible Assets

6 Months Ended

Jun. 30, 2018

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

7.	Intangible Assets

Intangible assets, net consisted of the following (in thousands):

	June 30,			December 31,
	2018			2017
Cost:
Internal-use software	$	1,199		$	1,314
Developed technology		522			522
Trademarks/trade names		201			201
Customer relationships		164			164
Total carrying value		2,086			2,201
Accumulated amortization:
Internal-use software		(964	)		(872	)
Developed technology		(291	)		(258	)
Trademarks/trade names		(89	)		(79	)
Customer relationships		(147	)		(130	)
Total accumulated amortization		(1,491	)		(1,339	)
Total intangible assets, net	$	595		$	862

The Company recorded amortization expense of $0.1 million for each of the three-month periods ended June 30, 2018 and 2017, which was included in amortization of intangible assets. The Company recorded amortization expense of $0.3 million for each of the six-month periods ended June 30, 2018 and 2017.

- Definition

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

+ References + Details

Accrued Compensation

6 Months Ended

Jun. 30, 2018

Accrued Compensation Disclosure [Abstract]

Accrued Compensation

8.	Accrued Compensation

Accrued compensation consisted of the following (in thousands):

	June 30,		December 31,
	2018		2017
Accrued payroll	$	10,519	$	13,064
Accrued commissions		7,496		7,928
Total accrued compensation	$	18,015	$	20,992

Accrued and Other Current Liabilities

6 Months Ended

Jun. 30, 2018

Payables And Accruals [Abstract]

Accrued and Other Current Liabilities

9.	Accrued and Other Current Liabilities

Accrued and other current liabilities consisted of the following (in thousands):

	June 30,		December 31,
	2018		2017
Current portion of lease pass-through financing obligation	$	4,985	$	4,931
Accrued unused commitment fees and interest		4,775		7,445
Accrued professional fees		4,338		3,977
Sales, use and property taxes payable		2,967		3,046
Accrued workers' compensation		2,555		1,446
Accrued inventory		1,818		4,122
Workmanship accrual		1,404		1,359
Current portion of deferred rent		927		937
Other accrued expenses		2,321		2,412
Total accrued and other current liabilities	$	26,090	$	29,675

Debt Obligations

6 Months Ended

Jun. 30, 2018

Debt Disclosure [Abstract]

Debt Obligations

10.	Debt Obligations

Debt obligations consisted of the following as of June 30, 2018 (in thousands, except interest rates):

	Principal		Unamortized Debt										Unused
	Borrowings		Issuance Costs						Net Carrying Value				Borrowing		Interest			Maturity
	Outstanding		Current			Long-term			Current		Long-term		Capacity		Rate			Date
Solar asset backed notes, Series 2018-1	$	466,000	$	(62	)	$	(9,555	)	$	2,979	$	453,404	$	—	*			October 2028
Solar asset backed notes, Series 2018-2⁽¹⁾⁽²⁾		345,000		(7	)		(7,991	)		293		336,709		—		5.2	%	August 2023
2017 Term loan facility		193,995		(170	)		(4,807	)		6,731		182,287		—		6.0		January 2035
Credit agreement		1,291		(2	)		(130	)		15		1,144		—		6.5		February 2023
Revolving lines of credit⁽³⁾
Aggregation facility		—		—			—			—		—		375,000		—		September 2020
Working capital facility⁽⁴⁾		136,500		—			—			—		136,500		—		5.3		March 2020
Total debt	$	1,142,786	$	(241	)	$	(22,483	)	$	10,018	$	1,110,044	$	375,000

Debt obligations consisted of the following as of December 31, 2017 (in thousands, except interest rates):

	Principal		Unamortized Debt										Unused
	Borrowings		Issuance Costs						Net Carrying Value				Borrowing		Interest			Maturity
	Outstanding		Current			Long-term			Current		Long-term		Capacity		Rate			Date
2017 Term loan facility	$	197,764	$	(176	)	$	(4,990	)	$	6,644	$	185,954	$	—		6.0	%	January 2035
2016 Term loan facility		287,919		(141	)		(7,623	)		4,962		275,193		—		4.3		August 2021
Subordinated HoldCo facility		197,625		(35	)		(3,451	)		1,965		192,174		—		9.3		March 2020
Credit agreement		1,299		(2	)		(140	)		14		1,143		—		6.5		February 2023
Revolving lines of credit⁽³⁾
Aggregation facility		135,000		—			—			—		135,000		240,000		4.7		September 2020
Working capital facility⁽⁴⁾		136,500		—			—			—		136,500		—		4.8		March 2020
Total debt	$	956,107	$	(354	)	$	(16,204	)	$	13,585	$	925,964	$	240,000


*	The Series 2018-1 Notes are comprised of Class A and Class B Notes. Class A Notes accrue interest at 4.73%. Class B Notes accrue interest at 7.37%.
(1)	The Series 2018-2 Notes are comprised of Class A and Class B Notes. Class B Notes accrue interest at a rate of LIBOR plus 4.75%. Class A Notes accrue interest at a variable spread over LIBOR that results in a weighted average spread for all 2018-2 Notes of 2.95%.
(2)	The interest rate of this facility is partially hedged to an effective interest rate of 6.0% for $327.8 million of the principal borrowings. See Note 11—Derivative Financial Instruments.
(3)	Revolving lines of credit are not presented net of unamortized debt issuance costs.
(4)	Facility is recourse debt, which refers to debt that is collateralized by the Company’s general assets. All of the Company’s other debt obligations are non-recourse, which refers to debt that is only collateralized by specified assets or subsidiaries of the Company.

The Company’s debt facilities include customary events of default, conditions to borrowing and covenants, including covenants that restrict, subject to certain exceptions, the Company’s ability to incur indebtedness, incur liens, make investments, make fundamental changes to their business, dispose of assets, make certain types of restricted payments or enter into certain related party transactions. Additionally, the Company is required to maintain certain financial measurements and interest rate swaps for certain debt facilities. These restrictions do not impact the Company’s ability to enter into investment funds, including those that are similar to those entered into previously. The Company’s debt facilities are secured by net cash flows from long-term customer contracts. The Company was in compliance with all debt covenants as of June 30, 2018.

Solar Asset Backed Notes, Series 2018-1

In June 2018, a wholly owned subsidiary of the Company issued an aggregate principal amount of $400.0 million of Solar Asset Backed Notes, Series 2018-1, Class A (the “2018-1 Class A Notes”) and an aggregate principal amount of $66.0 million of Solar Asset Backed Notes, Series 2018-1, Class B (the “2018-1 Class B Notes” and together with the 2018-1 Class A Notes, the “2018-1 Notes”). The 2018-1 Class A Notes accrue interest at a fixed rate of 4.73% and have an anticipated repayment date of October 30, 2028. The 2018-1 Class B Notes accrue interest at a fixed rate of 7.37% and have an anticipated repayment date of October 30, 2028.

In addition to customary events of default and covenants, the 2018-1 Notes are subject to unscheduled prepayment events that generally are customary in nature for solar securitizations of this type, including (1) asset coverage ratios falling below certain levels, (2) a debt service coverage ratio falling below certain levels, (3) the failure to maintain insurance, and (4) the failure to repay the notes in full prior to the anticipated repayment date for such class of notes. The occurrence of an unscheduled prepayment event or an event of default could result in the more rapid repayment of the 2018-1 Notes, and the occurrence of an event of default could, in certain instances, result in the liquidation of the collateral securing the 2018-1 Notes. The 2018-1 Notes are secured by, and payable solely from the cash flow generated by the membership interests in certain indirectly owned subsidiaries of the Company, each of which subsidiaries is the managing member of a project company that owns a pool of photovoltaic systems and related Solar Leases and PPAs and ancillary rights and agreements that were originated by a wholly owned subsidiary of the Company. As of June 30, 2018, the Company had $13.4 million in required reserves outstanding in collateral accounts with the administrative agent, which are included in restricted cash and cash equivalents.

Solar Asset Backed Notes, Series 2018-2

In June 2018, a wholly owned subsidiary of the Company issued an aggregate principal amount of $296.0 million of Solar Asset Backed Notes, Series 2018-2, Class A (the “2018-2 Class A Notes”) and an aggregate principal amount of $49.0 million of Solar Asset Backed Notes, Series 2018-2, Class B (the “2018-2 Class B Notes” and together with the 2018-2 Class A Notes, the “2018-2 Notes”). The 2018-2 Class A Notes accrue interest at a variable spread over the London Interbank Offered Rate (“LIBOR”) that is intended to result in a weighted average spread for all 2018-2 Notes of 2.95%. The 2018-2 Class B Notes accrue interest at a spread over LIBOR of 4.75% or, if no 2018-2 Class A Notes are outstanding, 2.95%. The Company entered into an interest rate swap concurrent with the issuance of the 2018-2 Notes that results in an implied all-in interest rate of approximately 5.95%. See Note 11—Derivative Financial Instruments. The 2018-2 Notes have a stated maturity of August 29, 2023.

The 2018-2 Notes have the same events of default, covenants and unscheduled prepayment events as the 2018-1 Notes. In addition, the 2018-2 Notes are subject to unscheduled prepayment events relating to certain change of control events and certain liquidity requirements. As of June 30, 2018, the Company had $23.9 million in required reserves outstanding in collateral accounts with the administrative agent, which are included in restricted cash and cash equivalents.

2016 Term Loan Facility

In June 2018, the Company used proceeds from the issuance of the 2018-1 Notes and 2018-2 Notes to pay off the outstanding balance of $282.3 million on the credit facility entered into by a wholly owned subsidiary of the Company in August 2016 (the “2016 Term Loan Facility”) and terminated the credit agreement. The outstanding balance was comprised of $281.8 million of principal and $0.5 million of accrued interest. The termination of the 2016 Term Loan Facility was accounted for as a debt extinguishment. As such, the remaining $6.9 million of unamortized debt issuance costs related to the 2016 Term Loan Facility were recognized in interest expense during the six months ended June 30, 2018. There was no prepayment fee associated with the termination of the 2016 Term Loan Facility.

Subordinated HoldCo Facility

In June 2018, the Company used proceeds from the issuance of the 2018-1 Notes and 2018-2 Notes to pay off the outstanding balance of $206.4 million on the credit facility entered into by a wholly owned subsidiary of the Company in March 2016 (the “Subordinated HoldCo Facility”) and terminated the financing agreement. The outstanding balance was comprised of $196.6 million of principal, $3.9 million of accrued interest, and a prepayment fee of $5.9 million, which was calculated as 3.0% of the outstanding principal balance. The termination of the Subordinated HoldCo Facility was accounted for as a debt extinguishment. As such, the remaining $2.9 million of unamortized debt issuance costs related to the Subordinated HoldCo Facility were recognized in interest expense during the six months ended June 30, 2018. The prepayment fee of $5.9 million was also recognized in interest expense during the six months ended June 30, 2018.

2017 Term Loan Facility

In January 2017, a wholly owned subsidiary of the Company entered into a long-term fixed rate credit agreement (the “2017 Term Loan Facility”). Interest on borrowings accrues at an annual fixed rate equal to 6.0% and is payable in arrears. Certain principal payments are due on a quarterly basis, subject to the occurrence of certain events. As of June 30, 2018, the Company had $19.3 million in required reserves outstanding in collateral accounts with the administrative agent, which were included in restricted cash and cash equivalents.

Credit Agreement

In February 2016, a wholly owned subsidiary of the Company entered into a fixed rate credit agreement (the “Credit Agreement”). Principal and interest payments under the Credit Agreement are paid quarterly over the term of the loan. Interest accrues on borrowings at a fixed rate of 6.50%.

Aggregation Facility

In September 2014, a wholly owned subsidiary of the Company entered into an aggregation credit facility (as amended, the “Aggregation Facility”), pursuant to which the Company may borrow up to an aggregate of $375.0 million and, upon the satisfaction of certain conditions and the approval of the lenders, up to an additional aggregate of $175.0 million in borrowings. Prepayments are permitted under the Aggregation Facility. Under the Aggregation Facility, interest on borrowings accrues at a floating rate equal to either (1)(a) LIBOR or (b) the greatest of (i) the Federal Funds Rate plus 0.5%, (ii) the administrative agent’s prime rate and (iii) LIBOR plus 1% and (2) a margin that varies between 3.25% during the period during which the Company may incur borrowings and 3.75% after such period. During the six months ended June 30, 2018, the Company used proceeds from the issuance of the 2018-1 Notes and 2018-2 Notes to pay off the outstanding balance on the Aggregation Facility such that there was no outstanding balance as of June 30, 2018. The Aggregation Facility remains open and available for future borrowings.

Working Capital Facility

In March 2015, a wholly owned subsidiary of the Company entered into a revolving credit agreement (the “Working Capital Facility”) pursuant to which the Company may borrow up to an aggregate principal amount of $150.0 million from certain financial institutions. In addition to the outstanding borrowings as of June 30, 2018, the Company had established letters of credit under the Working Capital Facility for up to $13.5 million related to insurance contracts. Prepayments are permitted under the Working Capital Facility. Interest accrues on borrowings at a floating rate equal to, depending on the type of borrowing, (1) a rate equal to the Eurodollar Rate for the interest period divided by one minus the Eurodollar Reserve Percentage, plus a margin of 3.25%; or (2) the highest of (a) the Federal Funds Rate plus 0.50%, (b) the Citibank prime rate and (c) the one-month interest period Eurodollar rate plus 1.00%, plus a margin of 2.25%. Interest is payable depending on the type of borrowing at the end of (1) the interest period that the Company may elect as a term, not to exceed three months, (2) quarterly or (3) at maturity of the Working Capital Facility. The Company is required to maintain $30.0 million in cash and cash equivalents and certain investments as of the last day of each quarter. As of June 30, 2018, the Company was in compliance with such covenants.

Derivative Financial Instruments

6 Months Ended

Jun. 30, 2018

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Financial Instruments

11.	Derivative Financial Instruments

Derivative financial instruments consisted of the following at fair value (in thousands):

	December 31, 2017
	Fair Value		Balance Sheet Location
Derivatives designated as hedging instruments:
Interest rate swaps	$	14,028	Other non-current assets, net
Derivatives not designated as hedging instruments:
Interest rate swaps	$	1,280	Other non-current liabilities

The Company is exposed to interest rate risk relating to its outstanding debt facilities that have variable interest rates. In connection with the 2016 Term Loan Facility, the Company entered into interest rate swaps to offset changes in the variable interest rate for a portion of the Company’s LIBOR-indexed floating-rate loans. During the six months ended June 30, 2018, the Company paid off and terminated the 2016 Term Loan Facility and settled all outstanding interest rate swaps associated with the 2016 Term Loan Facility. As a result of settling the interest rate swaps, which were designated as hedges, the Company realized a $22.5 million gain that was recorded as a reduction to interest expense.

In connection with the March 2017 amendment of the Aggregation Facility, the Company is required to maintain interest rate swaps such that at least 75% of the outstanding loan balance of the Aggregation Facility is hedged. The Company is required to meet this threshold within 15 business days after the end of each quarterly period. As of June 30, 2018, there was no outstanding balance in the Aggregation Facility, and as a result, the Company settled all outstanding interest rate swaps associated with the Aggregation Facility during the six months ended June 30, 2018. The settlement of the interest rate swaps, which were not designated as hedges, resulted in a realized gain of $2.0 million that was recorded as other income. The Aggregation Facility remains open and available for future borrowings, and the Company will open new interest rate swaps when it incurs future borrowings on the Aggregation Facility.

In connection with the 2018-2 Notes, the Company entered into interest rate swaps to offset changes in the variable interest rate for a portion of these notes. As of June 30, 2018, the notional amount of these interest rate swaps was $327.8 million. The notional amount of the interest rate swaps decreases through the maturity of the 2018-2 Notes, similar to the Company’s estimated semi-annual principal payments on the 2018-2 Notes through August 2023. The interest rate swaps are designated as cash flow hedges, and unrealized gains or losses are recorded in other comprehensive income (“OCI”). The amount of AOCI expected to be reclassified to interest expense within the next 12 months is approximately $1.5 million. The Company will discontinue the hedge accounting designation of these derivatives if interest payments on LIBOR-indexed floating rate loans compared to the payments under the derivatives are no longer highly effective.

The Company adopted ASU 2017-12 as of January 1, 2018. Among other changes, this update eliminated the separate measurement of hedge ineffectiveness. The Company adopted this update using a modified retrospective method with a cumulative-effect adjustment to retained earnings as of January 1, 2018. As a result, the Company ceased measuring hedge ineffectiveness beginning January 1, 2018, while prior period measurements remain unchanged. See Note 2—Summary of Significant Accounting Policies. The Company records derivatives at fair value. The (gains) losses on derivatives designated as cash flow hedges recognized in OCI, before tax effect, consisted of the following (in thousands):

	Three Months Ended June 30,
	2018		2017
Derivatives designated as cash flow hedges:
Interest rate swaps	$	825	$	1,813

	Six Months Ended June 30,
	2018			2017
Derivatives designated as cash flow hedges:
Interest rate swaps	$	(4,318	)	$	1,859

The (gains) losses on derivative financial instruments recognized in the condensed consolidated statements of operations, before tax effect, consisted of the following (in thousands):

	Three Months Ended June 30,
	2018						2017
	Interest expense			Other (income) expense, net			Interest expense			Other (income) expense, net
Total amounts presented in the income statement line items	$	11,336		$	(4,109	)	$	16,838		$	715

Derivatives designated as cash flow hedges:
Interest rate swaps
(Gains) reclassified from AOCI into income	$	(22,335	)	$	—		$	(6	)	$	—
Losses recognized in income - ineffective portion:		—			—			—			155
Derivatives not designated as hedging instruments:
Interest rate swaps
(Gains) losses recognized in income		—			(1,990	)		—			562
Total (gains) losses	$	(22,335	)	$	(1,990	)	$	(6	)	$	717

	Six Months Ended June 30,
	2018						2017
	Interest expense			Other (income) expense, net			Interest expense		Other (income) expense, net
Total amounts presented in the income statement line items	$	28,258		$	(6,370	)	$	31,559	$	991

Derivatives designated as cash flow hedges:
Interest rate swaps
(Gains) losses reclassified from AOCI into income	$	(22,716	)	$	—		$	144	$	—
(Gains) recognized in income - ineffective portion:		—			—			—		(521	)
Derivatives not designated as hedging instruments:
Interest rate swaps
(Gains) losses recognized in income		—			(4,252	)		—		1,514
Total (gains) losses	$	(22,716	)	$	(4,252	)	$	144	$	993

Investment Funds

6 Months Ended

Jun. 30, 2018

Summarized Financial Data Of Subsidiary [Abstract]

Investment Funds

12.	Investment Funds

As of June 30, 2018 and December 31, 2017, the Company had formed investment funds for the purpose of funding the purchase of solar energy systems under long-term customer contracts. The aggregate carrying value of these funds’ assets and liabilities (after elimination of intercompany transactions and balances) in the Company’s condensed consolidated balance sheets were as follows (in thousands):

	June 30,		December 31,
	2018		2017
Assets
Current assets:
Cash and cash equivalents	$	29,182	$	17,280
Accounts receivable, net		14,419		5,143
Prepaid expenses and other current assets		1,155		952
Total current assets		44,756		23,375
Solar energy systems, net		1,577,144		1,486,023
Other non-current assets, net		8,317		6,792
Total assets	$	1,630,217	$	1,516,190
Liabilities
Current liabilities:
Distributions payable to non-controlling interests and redeemable non-controlling interests	$	10,114	$	16,437
Current portion of deferred revenue		1,773		9,176
Accrued and other current liabilities		4,465		4,478
Total current liabilities		16,352		30,091
Deferred revenue, net of current portion		9,021		26,847
Other non-current liabilities		1,125		1,444
Total liabilities	$	26,498	$	58,382

Under the fund 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 fund investors and the Company’s subsidiaries as specified in contractual arrangements. As such, the cash held in investment funds is not readily available to the Company due to the timing of distributions. Certain of these fund arrangements have call and put options to acquire the investor’s equity interest as specified in the contractual agreements. Once the investor’s equity interest is acquired by the Company, the assets, liabilities and operations of the investment fund become wholly owned and no longer require an assessment of non-controlling interests.

Fund investors for three of the funds are managed indirectly by The Blackstone Group L.P. (the “Sponsor”) and are considered related parties. As of June 30, 2018 and December 31, 2017, the cumulative total of contributions into the VIEs by all investors was $1,372.9 million and $1,264.6 million. Of these contributions, a cumulative total of $110.0 million was contributed by related parties in prior periods. A third-party provider has agreed to perform backup maintenance services for all funds, if necessary.

Lease Pass-Through Financing Obligation

During 2015, a wholly owned subsidiary of the Company entered into a lease pass-through fund arrangement under which the Company contributed solar energy systems and the investor contributed cash. The net carrying value of the related solar energy systems was $57.0 million and $58.2 million as of June 30, 2018 and December 31, 2017.

The Company adopted Topic 606 as of January 1, 2018. The Company has assessed the impact of Topic 606 as it relates to the sales of ITCs through its lease pass-through fund arrangement. The Company has concluded that revenue related to the sale of ITCs through its lease pass-through arrangement is recognized when the related solar energy systems are placed in service as the Company has completed its performance obligation to transfer ITCs to the funds investors at that time. The fund investors contributed cash to the investment fund during the installation process as payment for the ITCs. The transaction price for the ITCs was estimated using the tax credit rate of 30% times the fair market value of the solar energy systems that were placed into service in the lease pass-through fund. All of the related solar energy systems were placed in service and all related revenue would have been recognized prior to September 30, 2016 under Topic 606. Prior to the adoption of Topic 606, the Company recognized this revenue evenly over the five-year ITC recapture period. The Company adopted Topic 606 on a modified retrospective basis with a cumulative adjustment to retained earnings as of January 1, 2018. As all ITC sales revenue would have been recognized prior to September 30, 2016 under Topic 606, the Company removed previously recorded deferred revenue related to ITC sales by recording it to retained earnings as of the adoption date of Topic 606. See Note 2—Summary of Significant Accounting Policies.

The Company accounts for the residual of the large upfront payments, net of amounts allocated to the ITCs, and subsequent periodic payments received from the fund investor as a borrowing by recording the proceeds received as a lease pass-through financing obligation, which will be repaid through customer payments that will be received by the investor. Under this approach, the Company continues to account for the arrangement with the customers in its condensed consolidated financial statements, whether the cash generated from the customer arrangements is received by the Company’s wholly owned subsidiary or paid directly to the fund investor. A portion of the amounts received by the fund investor from customer payments is applied to reduce the lease pass-through financing obligation, and the balance is allocated to interest expense. The customer payments are recognized into revenue based on cash receipts during the period as required by GAAP. Interest is calculated on the lease pass-through financing obligation using the effective interest rate method. The effective interest rate is the interest rate that equates the present value of the cash amounts to be received by a fund investor over the master lease term with the present value of the cash amounts paid by the investor to the Company, adjusted for any payments made by the Company. Any additional master lease prepayments by the investor would be recorded as an additional lease pass-through financing obligation, while any refunds of master lease prepayments would reduce the lease pass-through financing obligation.

The lease pass-through financing obligation is nonrecourse. As of June 30, 2018, the Company had recorded financing liabilities of $5.4 million related to this fund arrangement, which was the lease pass-through financing obligation recorded in other liabilities. As of December 31, 2017, the Company had recorded financing liabilities of $32.1 million related to this fund arrangement, of which $26.4 million was deferred revenue and $5.8 million was the lease pass-through financing obligation recorded in other liabilities.

Guarantees

With respect to the investment funds, the Company and the fund investors have entered into guaranty agreements under which the Company guarantees the performance of certain financial obligations of its subsidiaries to the investment funds. These guarantees do not result in the Company being required to make payments to the fund investors unless such payments are mandated by the investment fund governing documents and the investment fund fails to make such payment. Each of the Company’s investment funds and financing subsidiaries maintains separate books and records from each other and from the Company. The assets of each investment fund are not available to satisfy the debts or obligations of any other investment fund, subsidiary or the Company.

The Company is contractually obligated to make certain VIE investors whole for losses that the investors may suffer in certain limited circumstances resulting from the disallowance or recapture of ITCs. The Company has concluded that the likelihood of a significant recapture event is remote and consequently has not recorded any liability in the condensed consolidated financial statements for any potential recapture exposure. The maximum potential future payments that the Company could have to make under this obligation would depend on the Internal Revenue Service (“IRS”) successfully asserting upon audit that the fair market values of the solar energy systems sold or transferred to the funds as determined by the Company exceeded the allowable basis for the systems for purposes of claiming ITCs. The fair market values of the solar energy systems and related ITCs are determined and the ITCs are allocated to the fund investors in accordance with the funds’ governing agreements. Due to uncertainties associated with estimating the timing and amounts of distributions, the likelihood of an event that may trigger repayment, forfeiture or recapture of ITCs to such investors, and the fact that the Company cannot determine how the IRS will evaluate system values used in claiming ITCs, the Company cannot determine the potential maximum future payments that are required under these guarantees. As of June 30, 2018, the Company has not made any payments under these guarantees. However, several recent investment funds, the 2018-1 Notes and the 2018-2 Notes have required the Company to prepay insurance premiums to cover the risk of ITC recapture. The Company amortizes this prepaid insurance expense over the ITC recapture period. The Company had prepaid insurance balances of $8.8 million and $2.4 million as of June 30, 2018 and December 31, 2017.

From time to time, the Company incurs penalties for non-performance, which non-performance may include, but is not limited to, delays in the installation process and interconnection to the power grid of solar energy systems and other factors. Based on the terms of the investment fund agreements, the Company will either reimburse a portion of the fund investor’s capital or pay the fund investor a non-performance fee. Distributions paid to reimburse fund investors totaled $1.9 million and $11.9 million during the three and six months ended June 30, 2018. As of June 30, 2018, no accrual for additional distributions was required.

As a result of the guaranty arrangements in certain funds, the Company was required to hold a minimum cash balance of $10.0 million as of June 30, 2018 and December 31, 2017, which is classified as restricted cash and cash equivalents.

Redeemable Non-Controlling Interests and Equity

6 Months Ended

Jun. 30, 2018

Equity [Abstract]

Redeemable Non-Controlling Interests and Equity

13.	Redeemable Non-Controlling Interests and Equity

Common Stock

The Company had reserved shares of common stock for issuance as follows (in thousands):

	June 30,		December 31,
	2018		2017
Shares available for grant under equity incentive plans		14,267		12,774
Restricted stock units issued and outstanding		6,746		6,688
Stock options issued and outstanding		3,513		3,837
Long-term incentive plan		2,706		2,706
Total		27,232		26,005

Redeemable Non-Controlling Interests, Equity and Non-Controlling Interests

The changes in redeemable non-controlling interests were as follows (in thousands):

Balance as of December 31, 2017	$	122,444
Contributions from redeemable non-controlling interests		64,999
Distributions to redeemable non-controlling interests		(5,112	)
Net loss		(59,684	)
Balance as of June 30, 2018	$	122,647

The changes in stockholders’ equity and non-controlling interests were as follows (in thousands):

	Total
	Stockholders'			Non-Controlling
	Equity			Interests			Total Equity
Balance as of December 31, 2017	$	780,951		$	80,115		$	861,066
Cumulative-effect adjustment from adoption of new ASUs		(473,828	)		—			(473,828	)
Stock-based compensation expense		6,781			—			6,781
Issuance of common stock		837			—			837
Contributions from non-controlling interests		—			43,288			43,288
Distributions to non-controlling interests		—			(17,123	)		(17,123	)
Total other comprehensive loss		(13,408	)		—			(13,408	)
Net income (loss)		5,140			(65,530	)		(60,390	)
Balance as of June 30, 2018	$	306,473		$	40,750		$	347,223

Accumulated Other Comprehensive Income

The changes in AOCI are related to the Company’s cash flow hedges. The changes in AOCI, net of tax, were as follows (in thousands):

	Accumulated
	Other
	Comprehensive
	Income (Loss)
Balance as of December 31, 2017	$	6,905
Cumulative-effect adjustment from adoption of new ASUs		3,318
Other comprehensive income before reclassifications		3,147
Less: Amounts reclassified from AOCI		16,555
Balance as of June 30, 2018	$	(3,185	)

Redeemable Non-Controlling Interests and Non-Controlling Interests

Seven of the investment funds include a right for the non-controlling interest holder to require the Company’s wholly owned subsidiary to purchase all of its membership interests in the fund (each, a “Put Option”). The purchase price for the fund investor’s interest in the seven investment funds under the Put Options is the greater of fair market value at the time the option is exercised and a specified amount, ranging from $2.1 million to $4.1 million. The Put Options for these seven investment funds are exercisable beginning on the date that specified conditions are met for each respective fund. None of the Put Options are expected to become exercisable prior to 2021.

Because the Put Options represent redemption features that are not solely within the control of the Company, the non-controlling interests in these investment funds are presented outside of permanent equity. Redeemable non-controlling interests are recorded using the greater of their carrying value at each reporting date (which is impacted by attribution under the hypothetical liquidation at book value (“HLBV”) method) or their estimated redemption value in each reporting period.

In all investment funds except one, the Company’s wholly owned subsidiary has the right to require the non-controlling interest holder to sell all of its membership units to the Company’s wholly owned subsidiary (each, a “Call Option”). The purchase price for the fund investors’ interests under the Call Options varies by fund, but is generally the greater of a specified amount, which ranges from approximately $1.2 million to $7.0 million, the fair market value of such interest at the time the option is exercised, or an amount that causes the fund investor to achieve a specified return on investment. 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 2020.

Equity Compensation Plans

6 Months Ended

Jun. 30, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Equity Compensation Plans

14.	Equity Compensation Plans

Equity Incentive Plans

2014 Equity Incentive Plan

The Company currently grants equity awards through its 2014 Equity Incentive Plan (the “2014 Plan”). Under the 2014 Plan, the Company may grant stock options, restricted stock, restricted stock units (“RSUs”), stock appreciation rights, performance stock units, performance shares and performance awards to its employees, directors and consultants, and its parent and subsidiary corporations’ employees and consultants.

As of June 30, 2018, a total of 14.3 million shares of common stock were available to grant under the 2014 Plan, subject to adjustment in the case of certain events. The number of shares available to grant under the 2014 Plan is subject to an annual increase on the first day of each year. In accordance with the annual increase, an additional 4.6 million shares became available to grant in January 2018 under the 2014 Plan.

Stock Options

Stock Option Activity

Stock option activity for the six months ended June 30, 2018 was as follows (in thousands, except term and per share amounts):

						Weighted-
				Weighted-		Average
	Shares			Average		Remaining		Aggregate
	Underlying			Exercise		Contractual		Intrinsic
	Options			Price		Term (in years)		Value
Outstanding—December 31, 2017		3,837		$	2.01			$	8,522
Granted		517			3.15
Exercised		(749	)		1.12
Cancelled		(92	)		2.27
Outstanding—June 30, 2018		3,513		$	2.36		7.1	$	9,714
Options vested and exercisable—June 30, 2018		1,714		$	1.91		5.9	$	5,710

RSUs

RSU activity for the six months ended June 30, 2018 was as follows (awards in thousands):

				Weighted-
				Average
	Number of			Grant Date
	Awards			Fair Value
Outstanding at December 31, 2017		6,688		$	3.20
Granted		3,183			3.87
Vested		(2,629	)		2.80
Forfeited		(496	)		3.39
Outstanding at June 30, 2018		6,746		$	3.66

Stock-Based Compensation Expense

Stock-based compensation was included in operating expenses as follows (in thousands):

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
Cost of revenue	$	349	$	293	$	623	$	574
Sales and marketing		1,083		1,117		1,914		2,109
General and administrative		2,349		1,828		4,169		4,342
Research and development		31		92		75		227
Total stock-based compensation	$	3,812	$	3,330	$	6,781	$	7,252

Unrecognized stock-based compensation expense for time-based stock options and RSUs as of June 30, 2018 was as follows (in thousands, except years):

	Unrecognized		Weighted-
	Stock-Based		Average Period
	Compensation		of Recognition
	Expense		(in years)
RSUs	$	16,934		1.9
Time-based stock options		1,924		1.7
Total unrecognized stock-based compensation expense	$	18,858

The preceding table does not include $1.8 million of unrecognized stock-based compensation expense related to RSUs with performance conditions that the Company has determined are not probable of being achieved.

Income Taxes

6 Months Ended

Jun. 30, 2018

Income Tax Disclosure [Abstract]

Income Taxes

15.	Income Taxes

The income tax expense for the three months ended June 30, 2018 and 2017 was calculated on a discrete basis resulting in a consolidated quarterly effective income tax rate of (151.5)% and (16.2)%. For the six months ended June 30, 2018 and 2017 the Company’s consolidated effective income tax rate was (81.7)% and (18.7)% .The variations between the consolidated effective income tax rate and the U.S. federal statutory rate for the three and six months ended June 30, 2018 and 2017 were primarily attributable to the net effects of adopting ASU 2016-16, non-controlling interests and redeemable non-controlling interests, federal investment tax credits and the TCJA reducing the federal corporate income tax rate from 35% to 21% beginning in 2018.

The TCJA made significant changes to the U.S. tax code, which include, but are not limited to, a reduced U.S. federal corporate tax rate, a provision that limits the amount of deductible interest expense, full expensing of acquired property, limitations on the utilization of net operating loss carryforwards, the repeal of the domestic production activity deduction, limitations on the deductibility of certain executive compensation, and the tax year of income inclusion.

The Company recorded a provisional net tax benefit of $187.5 million related to the remeasurement of its deferred tax balances to reflect the corporate rate reduction in the period ended December 31, 2017. Although the Company is able to make a reasonable estimate of the impacts of the TCJA, it continues to analyze the temporary differences that existed on the date of enactment and the other previously mentioned provisions that come into effect for tax years starting after 2017 to determine if these items would impact the effective tax rate. The impact of the TCJA may differ from the Company’s estimates, possibly materially, due to, among other things, changes in interpretations and assumptions the Company has made, guidance that may be issued and actions the Company may take as a result of the TCJA.

The Company sells solar energy systems to the investment funds for income tax purposes. As the investment funds are consolidated by the Company, the gain on the sale of the solar energy systems is eliminated in the condensed consolidated financial statements. However, this gain is recognized for tax reporting purposes. With the adoption of ASU 2016-16, the Company now accounts for the income tax consequences of these intra-entity transfers, both current and deferred, as a component of income tax expense and deferred tax liability, net during the period in which the transfers occur. Prior to the adoption of ASU 2016-16, any tax expense incurred related to these intra-entity sales was deferred and amortized over the estimated useful life of the underlying solar energy systems, which was estimated to be 30 years. Accordingly, the Company had recorded a prepaid tax asset, net, of $505.9 million as of December 31, 2017, which was removed as of January 1, 2018 when the Company adopted ASU 2016-16. See Note 2—Summary of Significant Accounting Policies.

Uncertain Tax Positions

As of June 30, 2018 and December 31, 2017, the Company had no unrecognized tax benefits. There was no interest or penalties accrued for any uncertain tax positions as of June 30, 2018 and December 31, 2017. The Company does not have any tax positions for which it is reasonably possible the total amount of gross unrecognized benefits will increase or decrease within the next 12 months. The Company is subject to taxation and files income tax returns in the United States, and various state and local jurisdictions. The U.S. and state jurisdictions in which the Company operates have statutes of limitations that generally range from three to four years. The Company’s federal, state and local income tax returns starting with the 2014 tax year are subject to audit. The Company’s 2013 income tax returns for two states are also subject to audit.

Related Party Transactions

6 Months Ended

Jun. 30, 2018

Related Party Transactions

16.	Related Party Transactions

The Company’s condensed consolidated statements of operations included the following related party transactions (in thousands):

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
Cost of revenue—operating leases and incentives	$	—	$	233	$	—	$	631
Sales and marketing		610		564		1,311		1,262
General and administrative		—		49		—		124

Vivint Services

The Company has negotiated and entered into a number of agreements with its sister company, Vivint, Inc. (“Vivint”). Some of those agreements related to the Company’s use of certain of Vivint’s information technology and infrastructure services; however, the Company stopped using such services in July 2017. In August 2017, the Company entered into a sales dealer agreement with Vivint, pursuant to which each company will act as a non-exclusive dealer for the other party to market, promote and sell each other’s products. The agreement has an initial term of two years and replaces substantially all of the activities being undertaken under the parties’ former marketing and customer relations agreement. The Company and Vivint also agreed to extend the term of the non-solicitation provisions under an existing non-competition agreement to match the term of the sales dealer agreement. The Company incurred fees under agreements with Vivint of $4.3 million and $0.4 million for the three months ended June 30, 2018 and 2017, which reflect the amount of services provided by Vivint on behalf of the Company. The Company incurred fees under these agreements of $5.3 million and $1.1 million for the six months ended June 30, 2018 and 2017.

Payables to Vivint recorded in accounts payable—related party were $0.1 million and $0.2 million as of June 30, 2018 and December 31, 2017. These payables include amounts due to Vivint related to the services agreements and other miscellaneous intercompany payables.

Advances Receivable—Related Party

Net amounts due from direct-sales personnel were $5.3 million and $6.6 million as of June 30, 2018 and December 31, 2017. The Company provided a reserve of $1.0 million as of June 30, 2018 and December 31, 2017 related to advances to direct-sales personnel who have terminated their employment agreement with the Company.

Investment Funds

Fund investors for three of the investment funds are indirectly managed by the Sponsor and accordingly are considered related parties. The Company accrued equity distributions to these entities of $1.6 million and $1.2 million as of June 30, 2018 and December 31, 2017, included in distributions payable to non-controlling and redeemable non-controlling interests. See Note 12—Investment Funds.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2018

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

17.	Commitments and Contingencies

Non-Cancellable Operating Leases

The Company has entered into operating lease agreements for corporate and operating facilities, warehouses and related equipment in states in which the Company conducts operations. The aggregate expense incurred under these operating leases was $3.8 million and $4.1 million for the three months ended June 30, 2018 and 2017. The aggregate expense incurred under these operating leases was $7.7 million and $8.4 million for the six months ended June 30, 2018 and 2017.

Letters of Credit

As of June 30, 2018, the Company had established letters of credit under the Working Capital Facility for up to $13.5 million related to insurance contracts. See Note 10—Debt Obligations.

Indemnification Obligations

From time to time, the Company enters into contracts that contingently require it to indemnify parties against claims. These contracts primarily relate to provisions in the Company’s services agreements with related parties that may require the Company to indemnify the related parties against services rendered; and certain agreements with the Company’s officers and directors under which the Company may be required to indemnify such persons for liabilities. In addition, under the terms of the agreements related to the Company’s investment funds and other material contracts, the Company may also be required to indemnify fund investors and other third parties for liabilities. For further information see Note 12—Investment Funds.

Residual Commission Payments

The Company pays a portion of sales commissions to its sales representatives on a deferred basis. The amount deferred is based on the value of the system sold by the sales representative and payment is based on the sales representative remaining employed by the Company. As this amount is earned over time, it is not considered an initial direct cost of obtaining the contract due to the requirement that the sales representative remain in the Company’s service. As a result, the amount that is earned over time is expensed by the Company over the deferment period. As of June 30, 2018, the total estimated obligation that is currently not recorded in the Company’s condensed consolidated financial statements, but that will be earned and expensed over the deferment period was $7.1 million.

Legal Proceedings

In September 2015, two of the Company’s customers, on behalf of themselves and a purported class, named the Company in a putative class action, Case No. BCV-15-100925 (Cal. Super. Ct., Kern County), alleging violation of California Business and Professions Code Section 17200 and requesting relief pursuant to Section 1689 of the California Civil Code. The complaint sought: (1) rescission of their PPAs along with restitution to the plaintiffs individually and (2) declaratory and injunctive relief. In October 2015, the Company moved to compel arbitration of the plaintiffs’ claims pursuant to the provisions set forth in the PPAs, which the Court granted and dismissed the class claims without prejudice. The plaintiffs appealed the Court’s order. On July 26, 2017, the Court of Appeal for the Fifth Appellate District ruled that all issues concerning the interpretation, validity, or enforceability of the PPAs, including the arbitrability of class claims, must be submitted to arbitration. The appellate court vacated the portion of the trial court's order dismissing class claims, requiring that issue to be determined by an arbitrator. The case proceeded in arbitration administered by JAMS. In June 2018, the parties reached a settlement with the two individual plaintiffs.

In March 2016, the Company filed suit in the Court of Chancery State of Delaware against SunEdison and SEV Merger Sub Inc. alleging that SunEdison willfully breached its obligations under the Merger Agreement pursuant to which the Company was to be acquired and breached its implied covenant of good faith and fair dealing. In April 2016, SunEdison filed for Chapter 11 bankruptcy, which stayed prosecution of the Company’s litigation in the Delaware court. In September 2016, the Company submitted a proof of claim in the bankruptcy case for an unsecured claim in the initial amount of $1.0 billion, which was subject to dispute, for damages for breach of the Merger Agreement. In April 2018, the Company reached a settlement with the litigation trustee in the bankruptcy case under which the Company’s claim will be allowed in the amount of $590.0 million. This settlement resolves both the lawsuit in the Delaware Chancery Court and the dispute about the amount of the Company’s unsecured creditor claim in the bankruptcy. In April 2018, the Company received an initial distribution of $2.1 million and expects to receive further distributions as assets are distributed to unsecured creditors under the court-approved plan of reorganization in the SunEdison bankruptcy case. While the exact amount to be distributed for this claim is unknown at this time, the payout is expected to be a small fraction of the $590.0 million claim.

In November 2016, a customer of the Company filed a putative class action lawsuit in Superior Court in Alameda County, California, purportedly on behalf of all customers of a particular Company sales representative in California, claiming that the representative’s sales practices were improper under California consumer protection law. The Company moved to dismiss that action to compel arbitration. In March 2017, the original plaintiff filed an amended complaint adding an additional plaintiff, purporting to expand the proposed class to include all customers who are eligible for the California Alternate Rates for Energy program, and adding claims of misconduct in the Company’s sales practices apart from the individual representative identified in the original complaint. The Company moved to compel arbitration of the new plaintiff’s claims as well. The Company disputed the allegations in both the original and amended complaints. In January 2018, the parties reached a settlement with the two individual plaintiffs. Under the settlement, in addition to certain changes to its sales process and immaterial compensation payments to the individual plaintiffs, the Company agreed to pay attorneys’ fees. On May 29, 2018, the court entered an order requiring the Company to pay attorneys’ fees and costs, both of which have now been paid, and which were immaterial to the Company’s results of operations.

In March 2018, the New Mexico Attorney General’s office filed an action against the Company and several of its officers alleging violation of state consumer protection statutes and other claims. The Company disputes the allegations in the lawsuit and intends to defend itself in the action. The Company is unable to estimate a range of loss, if any, were there to be an adverse final decision. If an unfavorable outcome were to occur in this case, it is possible that the impact could be material to the Company’s results of operations in the period(s) in which any such outcome becomes probable and estimable.

In June 2018, four of the Company’s customers, on behalf of themselves and a purported class, named the Company in a putative class action alleging violations of the Consumers Legal Remedies Act and California Business and Professions Code Section 17200 and requesting relief pursuant to Section 1689 of the California Civil Code. The complaint sought (1) rescission of their PPAs along with restitution to the plaintiffs individually and (2) declaratory and injunctive relief. The Company disputes the allegations in the complaint and intends to vigorously defend itself. The Company is unable to estimate the amount or range of potential loss, if any, at this time.

In July 2018, an individual filed a putative class action lawsuit in the U.S. District Court for the District of Columbia, purportedly on behalf of himself and other persons who received certain telephone calls. The lawsuit alleges that the Company violated the Telephone Consumer Protection Act and some of its implementing regulations. The complaint seeks statutory penalties for each alleged violation. The Company disputes the allegations in the complaint and is in the process of retaining counsel to represent it in the litigation. The Company is unable to estimate the amount or range of potential loss, if any, at this time.

In addition to the matters discussed above, in the normal course of business, the Company has from time to time been named as a party to various legal claims, actions and complaints. While the outcome of these matters cannot be predicted with certainty, the Company does not currently believe that the outcome of any of these claims will have a material adverse effect, individually or in the aggregate, on its consolidated financial position, results of operations or cash flows.

The Company accrues for losses that are probable and can be reasonably estimated. The Company evaluates the adequacy of its legal reserves based on its assessment of many factors, including interpretations of the law and assumptions about the future outcome of each case based on available information.

Basic and Diluted Net Income (Loss) Per Share

6 Months Ended

Jun. 30, 2018

Earnings Per Share [Abstract]

Basic and Diluted Net Income (Loss) Per Share

18.	Basic and Diluted Net Income (Loss) Per Share

The following table sets forth the computation of the Company’s basic and diluted net income available (loss attributable) per share to common stockholders for the three and six months ended June 30, 2018 and 2017 (in thousands, except per share amounts):

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
Numerator:
Net income available to common stockholders	$	18,116	$	4,980	$	5,140	$	18,272
Denominator:
Shares used in computing net income available per share to common stockholders, basic		116,650		112,351		115,907		111,562
Weighted-average effect of potentially dilutive shares to purchase common stock		5,103		5,219		5,062		5,426
Shares used in computing net income available per share to common stockholders, diluted		121,753		117,570		120,969		116,988
Net income available per share to common stockholders:
Basic	$	0.16	$	0.04	$	0.04	$	0.16
Diluted	$	0.15	$	0.04	$	0.04	$	0.16

For the three months ended June 30, 2018 and 2017, 1.5 million shares and 1.4 million shares were excluded from the dilutive share calculations as the effect on net income per share would have been anti-dilutive. For the six months ended June 30, 2018 and 2017, 1.5 million shares and 1.1 million shares were excluded from the dilutive share calculations.

Subsequent Events

6 Months Ended

Jun. 30, 2018

Subsequent Events [Abstract]

Subsequent Events

19.	Subsequent Events

Investment Fund

In July 2018, a wholly owned subsidiary of the Company entered into an investment fund arrangement with a new fund investor. The total commitment under the investment fund arrangement is $50.0 million. The Company’s wholly owned subsidiary has the right to elect to require the fund investor to sell all of its membership units to the Company’s wholly owned subsidiary once certain conditions have been met. The purchase price for the fund investor’s interests is determined based on the fair market value of those interests at the time the option is exercised. The Company has not yet completed its assessment of whether the investment fund arrangement is a VIE.

Multi-Party Forward Flow Financing Transaction

On August 3, 2018 (the “Closing Date”), the Company and certain of its subsidiaries entered into a transaction to finance the purchase of residential solar energy systems, which included: (1) a senior secured loan facility with total commitments up to $130.0 million, (2) a levered tax equity investment fund with total commitments of $150.0 million, and (3) a cash equity investment fund with total commitments of $47.0 million (collectively, the “Transaction”). The Transaction will finance the installation of systems with an aggregate value of approximately $410 million, which the Company estimates will fund approximately 95 megawatts of future solar energy systems.

Loan Facility

Vivint Solar Asset 1 Project Company, LLC (“Borrower”), which is indirectly owned by the Company together with investors, entered into a loan agreement (the “Loan Agreement”) pursuant to which it may borrow up to an aggregate principal amount of $130.0 million with certain financial institutions for which Wells Fargo Bank, National Association is acting as administrative agent, collateral agent and depositary agent.

Borrower may make multiple borrowings under the loan agreement during the availability period, commencing on the Closing Date and continuing until late 2019 (the “Availability Period”). Proceeds of the loans will be used to (1) purchase residential solar projects from a wholly owned subsidiary of the Company, (2) fund certain reserve accounts, and (3) pay transaction costs and fees in connection with this transaction.

Interest on each loan will accrue at an annual rate equal to the U.S. swap rate for the weighted-average life of such loan, plus an applicable margin equal to the greater of (a) 1.90% plus a spread adjustment based on the risk premium on the borrowing date relative to the market index-based risk premium on the Closing Date and (b) 1.50%. Scheduled principal payments are due on a quarterly basis, at the end of January, April, July and October of each year.

Tax Equity Investment Fund

Vivint Solar Asset 1 Owner, LLC, which is indirectly owned by the Company together with investors, is a levered tax equity investment fund (the “Tax Equity Investment Fund”), which wholly owns the Borrower described above. The tax equity fund investors’ total commitment in the Tax Equity Investment Fund is $150.0 million. The tax equity fund investors’ contribution of capital and the obligation of the Tax Equity Investment Fund to purchase systems from the Company is subject to customary conditions precedent, covenants, indemnities, and events of default.

The Company through a wholly owned subsidiary has the right to elect to require the tax equity fund investors to sell all of their membership units in the Tax Equity Investment Fund to the Company upon satisfaction of certain conditions. The purchase price for the tax equity fund investors’ interests is determined based on the fair market value of those interests at the time the option is exercised.

Cash Equity Investment Fund

Vivint Solar Asset 1 Class B, LLC, which is indirectly owned by the Company together with an investor, is a cash equity investment fund, which has an ownership interest in the Tax Equity Investment Fund described above (the “Cash Equity Investment Fund”). The cash equity fund investor’s total commitment in the Cash Equity Investment Fund is $47.0 million. The cash equity fund investor’s contribution of capital and obligations in the Cash Equity Investment Fund are subject to customary conditions precedent, covenants, indemnities, and events of default.

The Company through a wholly owned subsidiary has the right to elect to require the cash equity fund investor to sell all of its membership units in the Cash Equity Investment Fund to the Company upon satisfaction of certain conditions. The purchase price for the cash equity fund investor’s interests is determined based on the fair market value of those interests at the time the option is exercised.

The Company has not yet completed its assessment of whether the tax equity investment fund or the cash equity investment fund arrangements are VIEs.

Summary of Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2018

Accounting Policies [Abstract]

Basis of Presentation and Principles of Consolidation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and applicable rules and regulations of the Securities and Exchange Commission regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. As such, these unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and accompanying notes included in the Company’s annual report on Form 10-K dated as of March 7, 2018. The unaudited condensed consolidated financial statements were prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, reflect all adjustments (all of which were considered of normal recurring nature) considered necessary to present fairly the Company’s financial results. The results of the six months ended June 30, 2018 are not necessarily indicative of the results to be expected for the fiscal year ending December 31, 2018 or for any other interim period or other future year.

The unaudited condensed consolidated financial statements reflect the accounts and operations of the Company and those of its subsidiaries in which the Company has a controlling financial interest. The Company uses a qualitative approach in assessing the consolidation requirement for variable interest entities (“VIEs”). This approach 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. All of these determinations involve significant management judgments and estimates. The Company has determined that it is the primary beneficiary in the operational VIEs in which it has an equity interest. The Company evaluates its relationships with the VIEs on an ongoing basis to ensure that it continues to be the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation. For additional information, see Note 12—Investment Funds.

Certain prior period amounts have been reclassified to conform to current year presentation. These reclassifications did not have a significant impact on the consolidated financial statements.

Use of Estimates

The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. The Company regularly makes significant estimates and assumptions including, but not limited to, investment tax credits (“ITCs”); revenue recognition; solar energy systems, net; the impairment analysis of long-lived assets; stock-based compensation; the provision for income taxes; the valuation of derivative financial instruments; the recognition and measurement of loss contingencies; and non-controlling interests and redeemable non-controlling interests. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could differ materially from those estimates.

Liquidity

In order to grow, the Company requires cash to finance the deployment of solar energy systems. As of the date of this filing, the Company will require additional sources of cash beyond current cash balances, and currently available financing facilities to fund long-term planned growth. If the Company is unable to secure additional financing when needed, or upon desirable terms, the Company may be unable to finance installation of customers’ systems in a manner consistent with past performance, cost of capital could increase, or the Company may be required to significantly reduce the scope of operations, any of which would have a material adverse effect on its business, financial condition, results of operations and prospects. While the Company believes additional financing is available and will continue to be available to support current levels of operations, the Company believes it has the ability and intent to reduce operations to the level of available financial resources for at least the next 12 months from the date of this report, if necessary.

Revenue from Contracts with Customers

The Company adopted ASU 2014-09, Revenue from Contracts with Customers, and its various updates (“Topic 606”) effective January 1, 2018 using the modified retrospective method with a cumulative adjustment to retained earnings as of January 1, 2018. As such, only the current period presented in the Company’s condensed consolidated statements of operations has been reported using the new revenue standard. The Company has applied Topic 606 to all customer contracts not completed by the initial date of application.

The Company currently accounts for PPAs, Solar Leases, and associated rebates and incentives as minimum lease payments from operating leases under ASC 840, Leases. However, the Company has determined that these agreements do not meet the definition of a lease under ASC 842, Leases, and these agreements will be accounted for in accordance with Topic 606 after the adoption of ASC 842. The revenue associated with these contracts with customers is currently shown together on the condensed consolidated statement of operations as revenue from operating leases and incentives. The Company will adopt ASC 842 effective January 1, 2019. The Company has determined that under Topic 606 there will be no change from current revenue recognition practices for its PPA revenue stream. For the Company’s Solar Leases, the Company has concluded that the impact of adopting Topic 606 will be immaterial. Revenue from all of the Company’s Solar Leases will be recognized on a straight-line basis over the contractual term; currently a significant majority of Solar Leases are already recognized on a straight-line basis. The Company has also concluded that there will be no material change related to the timing of revenue recognition for rebates and incentives.

The Company has analyzed the impact of Topic 606 on System Sales and other product sales and has concluded that the revenue recognition associated with these product sales did not change in the condensed consolidated financial statements. The Company will continue to show this revenue stream as solar energy system and product sales in the condensed consolidated statement of operations. The Company’s principal performance obligation for System Sales is to design and install a solar energy system that is interconnected to the local power grid and granted permission to operate to the customer. When the solar energy system has been granted permission to operate, the customer retains all of the significant risks and rewards of ownership of the solar energy system. For certain System Sales, the Company provides limited post-sale services to monitor the productivity of the solar energy system for 20 years after it has been placed in service. The Company collects cash during the installation process and recognizes revenue for System Sales and other product sales at the placed in-service date or product delivery date less any revenue allocated to monitoring services. The Company allocates a portion of the transaction price to the monitoring services by estimating the fair market price that the Company would charge for these services if offered separately from the sale of the solar energy system. As of June 30, 2018 and December 31, 2017, the Company had allocated deferred revenue of $2.7 million and $2.1 million to monitoring services that will be recognized over the term of the monitoring services. All costs to obtain and fulfill contracts associated with System Sales and other product sales are expensed as a cost of revenue when the Company has fulfilled its performance obligation and the products have been placed into service or delivered to the customer.

The Company has assessed the impact of Topic 606 as it relates to the sales of ITCs through its lease pass-through fund arrangement. The Company has concluded that revenue related to the sale of ITCs through its lease pass-through arrangement is recognized when the related solar energy systems are placed in service as the Company has completed its performance obligation to transfer ITCs to the fund investors at that time. The fund investors contributed cash to the investment fund during the installation process as payment for the ITCs. The transaction price for the ITCs was estimated using the tax credit rate of 30% multiplied by the fair market value of the solar energy systems that were placed into service in the lease pass-through fund. All of the related solar energy systems were placed in service and all related revenue would have been recognized prior to September 30, 2016 under Topic 606. Prior to the adoption of Topic 606, the Company recognized this revenue evenly over the five-year ITC recapture period. This earlier recognition of the ITC lease pass-through revenue decreased revenue for the three and six months ended June 30, 2018 by $0.9 million and $3.2 million and would have decreased revenue for the three and six months ended June 30, 2017 by $0.9 million and $3.2 million. As all ITC sales revenue would have been recognized prior to September 30, 2016 under Topic 606, there is no deferred revenue related to ITC sales recorded after the adoption date of January 1, 2018, and there would have been no deferred revenue as of December 31, 2017. As shown below, the cumulative adjustment related to ITC revenue recognized into retained earnings, net of tax, as of January 1, 2018 was $19.2 million.

As noted above, the Company adopted Topic 606 on a modified retrospective basis. However, if the Company adjusted the comparative period to reflect the adoption of Topic 606, the following adjustments would have been made to the condensed consolidated statement of operations for the three and six months ended June 30, 2017 (in thousands, except per share data):

	Three Months Ended June 30, 2017							Six Months Ended June 30, 2017
	As Previously		Revenue					As Previously		Revenue
	Reported		Adjustment			As Adjusted		Reported		Adjustment			As Adjusted
Revenue	$	72,995	$	(865	)	$	72,130	$	126,109	$	(3,229	)	$	122,880
Income tax expense		5,156		(234	)		4,922		14,557		(875	)		13,682
Net income available to common shareholders		4,980		(631	)		4,349		18,272		(2,354	)		15,918
Diluted earnings per share		0.04		(0.01	)		0.03		0.16		(0.02	)		0.14

Additionally, the following adjustments would have been made to the condensed consolidated balance sheet as of December 31, 2017 (in thousands):

	As Previously		Revenue
	Reported		Adjustment			As Adjusted
Current portion of deferred revenue	$	41,846	$	(7,707	)	$	34,139
Deferred revenue, net of current portion		29,200		(18,690	)		10,510
Deferred tax liability, net		342,382		7,160			349,542

Retained earnings		213,107		(19,237	)		193,870

Income Taxes

The Company adopted ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory (“ASU 2016-16”), effective January 1, 2018 using the modified retrospective method by removing the prepaid tax asset, net and recording a cumulative adjustment to retained earnings of $493.1 million and to deferred tax liability, net of $12.8 million as of January 1, 2018. As such, only the current periods presented in the Company’s condensed consolidated statements of operations have been reported using the new accounting standard. The Company now accounts for the income tax consequences of these intra-entity transfers, both current and deferred, as a component of income tax expense and deferred tax liability, net during the period in which the transfers occur.

The adoption of ASU 2016-16 had the following effect on the Company’s condensed consolidated statement of operations for the three and six months ended June 30, 2018 (in thousands, except per share data):

	Three Months Ended June 30, 2018									Six Months Ended June 30, 2018
	Pre-Adoption			Effect of						Pre-Adoption			Effect of
	Accounting			Adoption			As Reported			Accounting			Adoption			As Reported
Income tax expense	$	18,598		$	16,754		$	35,352		$	24,379		$	29,616		$	53,995
Net loss		(41,936	)		(16,754	)		(58,690	)		(90,458	)		(29,616	)		(120,074	)
Net loss attributable to common shareholders		34,870			(16,754	)		18,116			34,756			(29,616	)		5,140
Basic earnings per share		0.30			(0.14	)		0.16			0.30			(0.26	)		0.04
Diluted earnings per share		0.29			(0.14	)		0.15			0.29			(0.25	)		0.04

The Company adopted ASU 2018-02, Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (“ASU 2018-02”), effective January 1, 2018. As permitted by ASU 2018-02, the Company has elected to reclassify the income tax effects of the Tax Cuts and Jobs Act (the “TCJA”) on items within accumulated other comprehensive income (“AOCI”) to retained earnings. The Company applied the amendments in this update in the period of adoption. The total amount the Company reclassified to retained earnings as a result of adopting ASU 2018-02 was approximately $1.5 million. After applying this update, the Company had no stranded tax effects remaining in AOCI.

Derivative Financial Instruments

The Company adopted ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities (“ASU 2017-12”), effective January 1, 2018. This update made targeted improvements to accounting for hedging activities by simplifying certain documentation and assessment requirements and eliminating the requirement to separately measure and report hedge ineffectiveness. The Company applied this update using a modified retrospective method to eliminate the separate measurement of hedge ineffectiveness by recording a cumulative-effect adjustment to retained earnings as of January 1, 2018. The net amount the Company recorded to retained earnings as a result of adopting ASU 2017-12 was approximately $1.8 million.

Restricted Cash

The Company adopted ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force) (“ASU 2016-18”), effective January 1, 2018. This update clarified that transfers between cash and restricted cash are not reported as cash flow activities in the statements of cash flows. As such, restricted cash amounts are included with cash and cash equivalents in the beginning-of-period and end-of-period total amounts on the statements of cash flows. The Company applied this update retrospectively, which resulted in an adjustment to the beginning-of-period and end-of-period total amounts on the condensed consolidated statement of cash flows for the six months ended June 30, 2017 to include restricted cash balances from those periods.

Recent Accounting Pronouncements

In July 2018, the Financial Accounting Standards Board (the “FASB”) issued ASU 2018-10 and ASU 2018-11, which clarify aspects of the guidance in ASU 2016-02, Leases (Topic 842). The objective of ASU 2016-02 is to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. This update primarily changes the recognition by lessees of lease assets and liabilities for leases currently classified as operating leases. Lessor accounting remains largely unchanged. This update is effective in fiscal years beginning after December 15, 2018 for public business entities and early adoption is permitted. The amendments are required to be applied using a modified retrospective approach. However, ASU 2018-11 provides an additional transition method under which an entity will apply the updates in ASU 2016-02 as of the adoption date with a cumulative-effect adjustment to the opening balance of retained earnings. Under this additional transition method, periods ending prior to January 1, 2019 will be presented in accordance with ASC 840, and periods ending after January 1, 2019 will be presented in accordance with ASC 842. The Company will adopt this standard effective January 1, 2019 and plans to utilize the transition method permitted by ASU 2018-11. The Company has operating leases that will be affected by this update and the Company is still evaluating the full impact on its condensed consolidated financial statements and related disclosures. The impact is not expected to be significant to the Company’s condensed consolidated financial statements.

In June 2018, the FASB issued ASU 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. This update expands the scope of Topic 718 to include share-based payments to nonemployees. Under current guidance, the measurement date for nonemployee equity awards is not established until the nonemployee’s performance is complete. This update states that the measurement date for nonemployee equity awards will now be established at the grant date. This amendment is effective for annual periods beginning after December 15, 2018 and is applied through a modified retrospective method with a cumulative-effect adjustment to retained earnings as of the beginning of the fiscal year of adoption. The Company has outstanding nonemployee equity awards that will be affected by this update. The impact to the Company will not be known until the date of adoption, as it will depend on the Company’s stock price on the adoption date. However, the Company currently marks all nonemployee awards to market at each reporting period and as such, the impact is not expected to be significant.

- Definition

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.

+ References + Details

Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2018

ASU 2014-09

Schedule of Accounting Standards Update Adjustments to Financial Statements

As noted above, the Company adopted Topic 606 on a modified retrospective basis. However, if the Company adjusted the comparative period to reflect the adoption of Topic 606, the following adjustments would have been made to the condensed consolidated statement of operations for the three and six months ended June 30, 2017 (in thousands, except per share data):

	Three Months Ended June 30, 2017							Six Months Ended June 30, 2017
	As Previously		Revenue					As Previously		Revenue
	Reported		Adjustment			As Adjusted		Reported		Adjustment			As Adjusted
Revenue	$	72,995	$	(865	)	$	72,130	$	126,109	$	(3,229	)	$	122,880
Income tax expense		5,156		(234	)		4,922		14,557		(875	)		13,682
Net income available to common shareholders		4,980		(631	)		4,349		18,272		(2,354	)		15,918
Diluted earnings per share		0.04		(0.01	)		0.03		0.16		(0.02	)		0.14

Additionally, the following adjustments would have been made to the condensed consolidated balance sheet as of December 31, 2017 (in thousands):

	As Previously		Revenue
	Reported		Adjustment			As Adjusted
Current portion of deferred revenue	$	41,846	$	(7,707	)	$	34,139
Deferred revenue, net of current portion		29,200		(18,690	)		10,510
Deferred tax liability, net		342,382		7,160			349,542

Retained earnings		213,107		(19,237	)		193,870

ASU 2016-16

Schedule of Accounting Standards Update Adjustments to Financial Statements

The adoption of ASU 2016-16 had the following effect on the Company’s condensed consolidated statement of operations for the three and six months ended June 30, 2018 (in thousands, except per share data):

	Three Months Ended June 30, 2018									Six Months Ended June 30, 2018
	Pre-Adoption			Effect of						Pre-Adoption			Effect of
	Accounting			Adoption			As Reported			Accounting			Adoption			As Reported
Income tax expense	$	18,598		$	16,754		$	35,352		$	24,379		$	29,616		$	53,995
Net loss		(41,936	)		(16,754	)		(58,690	)		(90,458	)		(29,616	)		(120,074	)
Net loss attributable to common shareholders		34,870			(16,754	)		18,116			34,756			(29,616	)		5,140
Basic earnings per share		0.30			(0.14	)		0.16			0.30			(0.26	)		0.04
Diluted earnings per share		0.29			(0.14	)		0.15			0.29			(0.25	)		0.04

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2018

Fair Value Disclosures [Abstract]

Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis

The Company measures and reports its cash equivalents at fair value. The following tables set forth the fair value of the Company’s financial assets and liabilities measured on a recurring basis by level within the fair value hierarchy (in thousands):

	June 30, 2018
	Level 1		Level 2		Level 3		Total
Financial Liabilities
Interest rate swaps	$	—	$	4,370	$	—	$	4,370

	December 31, 2017
	Level 1		Level 2		Level 3		Total
Financial Assets
Interest rate swaps	$	—	$	14,028	$	—	$	14,028

Financial Liabilities
Interest rate swaps	$	—	$	1,280	$	—	$	1,280

Schedule of Carrying Values and Fair Values of Company's Long-term Debt

The carrying values and fair values of the Company’s long-term debt were as follows (in thousands):

	June 30, 2018				December 31, 2017
	Carrying Value		Fair Value		Carrying Value		Fair Value
Floating-rate long-term debt	$	481,500	$	481,500	$	757,044	$	757,044
Fixed-rate long-term debt		661,286		684,532		199,063		238,618
Total	$	1,142,786	$	1,166,032	$	956,107	$	995,662

Inventories (Tables)

6 Months Ended

Jun. 30, 2018

Inventory Disclosure [Abstract]

Summary of Inventories

Inventories consisted of the following (in thousands):

	June 30,		December 31,
	2018		2017
Solar energy systems held for sale	$	12,113	$	21,971
Photovoltaic installation products		1,022		626
Total inventories	$	13,135	$	22,597

Solar Energy Systems (Tables)

6 Months Ended

Jun. 30, 2018

Solar Energy Systems Disclosure [Abstract]

Solar Energy Systems

Solar energy systems, net consisted of the following (in thousands):

	June 30,			December 31,
	2018			2017
System equipment costs	$	1,540,791		$	1,437,419
Initial direct costs related to solar energy systems		375,759			336,136
		1,916,550			1,773,555
Less: Accumulated depreciation and amortization		(161,124	)		(129,640	)
		1,755,426			1,643,915
Solar energy system inventory		29,374			29,617
Solar energy systems, net	$	1,784,800		$	1,673,532

Property and Equipment (Tables)

6 Months Ended

Jun. 30, 2018

Property Plant And Equipment [Abstract]

Summary of Property and Equipment Net

Property and equipment, net consisted of the following (in thousands):

	Estimated	June 30,			December 31,
	Useful Lives	2018			2017
Vehicles acquired under capital leases	3-5 years	$	11,403		$	15,113
Leasehold improvements	1-12 years		12,301			15,071
Furniture and computer and other equipment	3 years		4,115			6,492
			27,819			36,676
Less: Accumulated depreciation and amortization			(15,801	)		(21,598	)
Property and equipment, net		$	12,018		$	15,078

Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2018

Goodwill And Intangible Assets Disclosure [Abstract]

Summary of Intangible Assets, Net

Intangible assets, net consisted of the following (in thousands):

	June 30,			December 31,
	2018			2017
Cost:
Internal-use software	$	1,199		$	1,314
Developed technology		522			522
Trademarks/trade names		201			201
Customer relationships		164			164
Total carrying value		2,086			2,201
Accumulated amortization:
Internal-use software		(964	)		(872	)
Developed technology		(291	)		(258	)
Trademarks/trade names		(89	)		(79	)
Customer relationships		(147	)		(130	)
Total accumulated amortization		(1,491	)		(1,339	)
Total intangible assets, net	$	595		$	862

Accrued Compensation (Tables)

6 Months Ended

Jun. 30, 2018

Accrued Compensation Disclosure [Abstract]

Summary of Accrued Compensation

Accrued compensation consisted of the following (in thousands):

	June 30,		December 31,
	2018		2017
Accrued payroll	$	10,519	$	13,064
Accrued commissions		7,496		7,928
Total accrued compensation	$	18,015	$	20,992

Accrued and Other Current Liabilities (Tables)

6 Months Ended

Jun. 30, 2018

Payables And Accruals [Abstract]

Schedule of Accrued and Other Current Liabilities

Accrued and other current liabilities consisted of the following (in thousands):

	June 30,		December 31,
	2018		2017
Current portion of lease pass-through financing obligation	$	4,985	$	4,931
Accrued unused commitment fees and interest		4,775		7,445
Accrued professional fees		4,338		3,977
Sales, use and property taxes payable		2,967		3,046
Accrued workers' compensation		2,555		1,446
Accrued inventory		1,818		4,122
Workmanship accrual		1,404		1,359
Current portion of deferred rent		927		937
Other accrued expenses		2,321		2,412
Total accrued and other current liabilities	$	26,090	$	29,675

Debt Obligations (Tables)

6 Months Ended

Jun. 30, 2018

Debt Disclosure [Abstract]

Schedule of Debt

Debt obligations consisted of the following as of June 30, 2018 (in thousands, except interest rates):

	Principal		Unamortized Debt										Unused
	Borrowings		Issuance Costs						Net Carrying Value				Borrowing		Interest			Maturity
	Outstanding		Current			Long-term			Current		Long-term		Capacity		Rate			Date
Solar asset backed notes, Series 2018-1	$	466,000	$	(62	)	$	(9,555	)	$	2,979	$	453,404	$	—	*			October 2028
Solar asset backed notes, Series 2018-2⁽¹⁾⁽²⁾		345,000		(7	)		(7,991	)		293		336,709		—		5.2	%	August 2023
2017 Term loan facility		193,995		(170	)		(4,807	)		6,731		182,287		—		6.0		January 2035
Credit agreement		1,291		(2	)		(130	)		15		1,144		—		6.5		February 2023
Revolving lines of credit⁽³⁾
Aggregation facility		—		—			—			—		—		375,000		—		September 2020
Working capital facility⁽⁴⁾		136,500		—			—			—		136,500		—		5.3		March 2020
Total debt	$	1,142,786	$	(241	)	$	(22,483	)	$	10,018	$	1,110,044	$	375,000

Debt obligations consisted of the following as of December 31, 2017 (in thousands, except interest rates):

	Principal		Unamortized Debt										Unused
	Borrowings		Issuance Costs						Net Carrying Value				Borrowing		Interest			Maturity
	Outstanding		Current			Long-term			Current		Long-term		Capacity		Rate			Date
2017 Term loan facility	$	197,764	$	(176	)	$	(4,990	)	$	6,644	$	185,954	$	—		6.0	%	January 2035
2016 Term loan facility		287,919		(141	)		(7,623	)		4,962		275,193		—		4.3		August 2021
Subordinated HoldCo facility		197,625		(35	)		(3,451	)		1,965		192,174		—		9.3		March 2020
Credit agreement		1,299		(2	)		(140	)		14		1,143		—		6.5		February 2023
Revolving lines of credit⁽³⁾
Aggregation facility		135,000		—			—			—		135,000		240,000		4.7		September 2020
Working capital facility⁽⁴⁾		136,500		—			—			—		136,500		—		4.8		March 2020
Total debt	$	956,107	$	(354	)	$	(16,204	)	$	13,585	$	925,964	$	240,000


*	The Series 2018-1 Notes are comprised of Class A and Class B Notes. Class A Notes accrue interest at 4.73%. Class B Notes accrue interest at 7.37%.
(1)	The Series 2018-2 Notes are comprised of Class A and Class B Notes. Class B Notes accrue interest at a rate of LIBOR plus 4.75%. Class A Notes accrue interest at a variable spread over LIBOR that results in a weighted average spread for all 2018-2 Notes of 2.95%.
(2)	The interest rate of this facility is partially hedged to an effective interest rate of 6.0% for $327.8 million of the principal borrowings. See Note 11—Derivative Financial Instruments.
(3)	Revolving lines of credit are not presented net of unamortized debt issuance costs.
(4)	Facility is recourse debt, which refers to debt that is collateralized by the Company’s general assets. All of the Company’s other debt obligations are non-recourse, which refers to debt that is only collateralized by specified assets or subsidiaries of the Company.

Derivative Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2018

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Schedule of Derivative Financial Instruments at Fair Value

Derivative financial instruments consisted of the following at fair value (in thousands):

	December 31, 2017
	Fair Value		Balance Sheet Location
Derivatives designated as hedging instruments:
Interest rate swaps	$	14,028	Other non-current assets, net
Derivatives not designated as hedging instruments:
Interest rate swaps	$	1,280	Other non-current liabilities

Schedule of (Gains) Losses on Derivative Financial Instruments Recognized in OCI and Condensed Consolidated Statements of Operations Before Tax Effect

The (gains) losses on derivatives designated as cash flow hedges recognized in OCI, before tax effect, consisted of the following (in thousands):

	Three Months Ended June 30,
	2018		2017
Derivatives designated as cash flow hedges:
Interest rate swaps	$	825	$	1,813

	Six Months Ended June 30,
	2018			2017
Derivatives designated as cash flow hedges:
Interest rate swaps	$	(4,318	)	$	1,859

The (gains) losses on derivative financial instruments recognized in the condensed consolidated statements of operations, before tax effect, consisted of the following (in thousands):

	Three Months Ended June 30,
	2018						2017
	Interest expense			Other (income) expense, net			Interest expense			Other (income) expense, net
Total amounts presented in the income statement line items	$	11,336		$	(4,109	)	$	16,838		$	715

Derivatives designated as cash flow hedges:
Interest rate swaps
(Gains) reclassified from AOCI into income	$	(22,335	)	$	—		$	(6	)	$	—
Losses recognized in income - ineffective portion:		—			—			—			155
Derivatives not designated as hedging instruments:
Interest rate swaps
(Gains) losses recognized in income		—			(1,990	)		—			562
Total (gains) losses	$	(22,335	)	$	(1,990	)	$	(6	)	$	717

	Six Months Ended June 30,
	2018						2017
	Interest expense			Other (income) expense, net			Interest expense		Other (income) expense, net
Total amounts presented in the income statement line items	$	28,258		$	(6,370	)	$	31,559	$	991

Derivatives designated as cash flow hedges:
Interest rate swaps
(Gains) losses reclassified from AOCI into income	$	(22,716	)	$	—		$	144	$	—
(Gains) recognized in income - ineffective portion:		—			—			—		(521	)
Derivatives not designated as hedging instruments:
Interest rate swaps
(Gains) losses recognized in income		—			(4,252	)		—		1,514
Total (gains) losses	$	(22,716	)	$	(4,252	)	$	144	$	993

Investment Funds (Tables)

6 Months Ended

Jun. 30, 2018

Schedule Of Investments [Abstract]

Aggregate Carrying Value of Funds Assets and Liabilities

As of June 30, 2018 and December 31, 2017, the Company had formed investment funds for the purpose of funding the purchase of solar energy systems under long-term customer contracts. The aggregate carrying value of these funds’ assets and liabilities (after elimination of intercompany transactions and balances) in the Company’s condensed consolidated balance sheets were as follows (in thousands):

	June 30,		December 31,
	2018		2017
Assets
Current assets:
Cash and cash equivalents	$	29,182	$	17,280
Accounts receivable, net		14,419		5,143
Prepaid expenses and other current assets		1,155		952
Total current assets		44,756		23,375
Solar energy systems, net		1,577,144		1,486,023
Other non-current assets, net		8,317		6,792
Total assets	$	1,630,217	$	1,516,190
Liabilities
Current liabilities:
Distributions payable to non-controlling interests and redeemable non-controlling interests	$	10,114	$	16,437
Current portion of deferred revenue		1,773		9,176
Accrued and other current liabilities		4,465		4,478
Total current liabilities		16,352		30,091
Deferred revenue, net of current portion		9,021		26,847
Other non-current liabilities		1,125		1,444
Total liabilities	$	26,498	$	58,382

- Definition

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

+ References + Details

Redeemable Non-Controlling Interests and Equity (Tables)

6 Months Ended

Jun. 30, 2018

Noncontrolling Interest [Abstract]

Schedule of Reserved Shares of Common Stock for Issuance

The Company had reserved shares of common stock for issuance as follows (in thousands):

	June 30,		December 31,
	2018		2017
Shares available for grant under equity incentive plans		14,267		12,774
Restricted stock units issued and outstanding		6,746		6,688
Stock options issued and outstanding		3,513		3,837
Long-term incentive plan		2,706		2,706
Total		27,232		26,005

Schedule of Changes in Redeemable Non-Controlling Interests

The changes in redeemable non-controlling interests were as follows (in thousands):

Balance as of December 31, 2017	$	122,444
Contributions from redeemable non-controlling interests		64,999
Distributions to redeemable non-controlling interests		(5,112	)
Net loss		(59,684	)
Balance as of June 30, 2018	$	122,647

Schedule of Changes in Total Stockholders' Equity and Non-Controlling Interests

The changes in stockholders’ equity and non-controlling interests were as follows (in thousands):

	Total
	Stockholders'			Non-Controlling
	Equity			Interests			Total Equity
Balance as of December 31, 2017	$	780,951		$	80,115		$	861,066
Cumulative-effect adjustment from adoption of new ASUs		(473,828	)		—			(473,828	)
Stock-based compensation expense		6,781			—			6,781
Issuance of common stock		837			—			837
Contributions from non-controlling interests		—			43,288			43,288
Distributions to non-controlling interests		—			(17,123	)		(17,123	)
Total other comprehensive loss		(13,408	)		—			(13,408	)
Net income (loss)		5,140			(65,530	)		(60,390	)
Balance as of June 30, 2018	$	306,473		$	40,750		$	347,223

Schedule Changes in Accumulated Other Comprehensive Income Related to Cash Flow Hedges

The changes in AOCI are related to the Company’s cash flow hedges. The changes in AOCI, net of tax, were as follows (in thousands):

	Accumulated
	Other
	Comprehensive
	Income (Loss)
Balance as of December 31, 2017	$	6,905
Cumulative-effect adjustment from adoption of new ASUs		3,318
Other comprehensive income before reclassifications		3,147
Less: Amounts reclassified from AOCI		16,555
Balance as of June 30, 2018	$	(3,185	)

Equity Compensation Plans (Tables)

6 Months Ended

Jun. 30, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity

Stock option activity for the six months ended June 30, 2018 was as follows (in thousands, except term and per share amounts):

						Weighted-
				Weighted-		Average
	Shares			Average		Remaining		Aggregate
	Underlying			Exercise		Contractual		Intrinsic
	Options			Price		Term (in years)		Value
Outstanding—December 31, 2017		3,837		$	2.01			$	8,522
Granted		517			3.15
Exercised		(749	)		1.12
Cancelled		(92	)		2.27
Outstanding—June 30, 2018		3,513		$	2.36		7.1	$	9,714
Options vested and exercisable—June 30, 2018		1,714		$	1.91		5.9	$	5,710

RSU Activity

RSU activity for the six months ended June 30, 2018 was as follows (awards in thousands):

				Weighted-
				Average
	Number of			Grant Date
	Awards			Fair Value
Outstanding at December 31, 2017		6,688		$	3.20
Granted		3,183			3.87
Vested		(2,629	)		2.80
Forfeited		(496	)		3.39
Outstanding at June 30, 2018		6,746		$	3.66

Summary of Stock-Based Compensation Expense

Stock-based compensation was included in operating expenses as follows (in thousands):

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
Cost of revenue	$	349	$	293	$	623	$	574
Sales and marketing		1,083		1,117		1,914		2,109
General and administrative		2,349		1,828		4,169		4,342
Research and development		31		92		75		227
Total stock-based compensation	$	3,812	$	3,330	$	6,781	$	7,252

Summary of Unrecognized Stock-Based Compensation Expense

Unrecognized stock-based compensation expense for time-based stock options and RSUs as of June 30, 2018 was as follows (in thousands, except years):

	Unrecognized		Weighted-
	Stock-Based		Average Period
	Compensation		of Recognition
	Expense		(in years)
RSUs	$	16,934		1.9
Time-based stock options		1,924		1.7
Total unrecognized stock-based compensation expense	$	18,858

Related Party Transactions (Tables)

6 Months Ended

Jun. 30, 2018

Components of Related Party Transactions

The Company’s condensed consolidated statements of operations included the following related party transactions (in thousands):

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
Cost of revenue—operating leases and incentives	$	—	$	233	$	—	$	631
Sales and marketing		610		564		1,311		1,262
General and administrative		—		49		—		124

Basic and Diluted Net Income (Loss) Per Share (Tables)

6 Months Ended

Jun. 30, 2018

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Income (Loss) Per Share to Common Stockholders

The following table sets forth the computation of the Company’s basic and diluted net income available (loss attributable) per share to common stockholders for the three and six months ended June 30, 2018 and 2017 (in thousands, except per share amounts):

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2018		2017		2018		2017
Numerator:
Net income available to common stockholders	$	18,116	$	4,980	$	5,140	$	18,272
Denominator:
Shares used in computing net income available per share to common stockholders, basic		116,650		112,351		115,907		111,562
Weighted-average effect of potentially dilutive shares to purchase common stock		5,103		5,219		5,062		5,426
Shares used in computing net income available per share to common stockholders, diluted		121,753		117,570		120,969		116,988
Net income available per share to common stockholders:
Basic	$	0.16	$	0.04	$	0.04	$	0.16
Diluted	$	0.15	$	0.04	$	0.04	$	0.16

Organization - Additional Information (Details)	6 Months Ended
Organization - Additional Information (Details)	Jun. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Contractual term of customers	20 years

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)		3 Months Ended		6 Months Ended
	Jan. 02, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Summary Of Significant Accounting Policies [Line Items]
Investment tax credit percentage of qualified assets				30.00%
Recapture period of revenue recognition				5 years
Effect of adopting new accounting pronouncements				$ 473,828,000
ASU 2014-09
Summary Of Significant Accounting Policies [Line Items]
Cumulative effect adjustment, retained earnings	$ 19,200,000
ASU 2016-16
Summary Of Significant Accounting Policies [Line Items]
Cumulative effect adjustment, retained earnings	493,100,000
Cumulative effect adjustment, deferred tax liability, net	12,800,000
ASU 2018-02
Summary Of Significant Accounting Policies [Line Items]
Cumulative effect adjustment, retained earnings	1,500,000
ASU 2017-12
Summary Of Significant Accounting Policies [Line Items]
Cumulative effect adjustment, retained earnings	$ 1,800,000
Calculated under Revenue Guidance in Effect before Topic 606
Summary Of Significant Accounting Policies [Line Items]
Deferred revenue							$ 0
Effect of adopting new accounting pronouncements		$ 900,000	$ 900,000	3,200,000	$ 3,200,000
Difference between Revenue Guidance in Effect before and after Topic 606
Summary Of Significant Accounting Policies [Line Items]
Deferred revenue						$ 0
Monitoring Services
Summary Of Significant Accounting Policies [Line Items]
Deferred revenue		$ 2,700,000		$ 2,700,000			$ 2,100,000

Summary of Significant Accounting Policies - Adjustments made to Condensed Consolidated Statement of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Revenue	$ 80,798	$ 72,995	$ 149,048	$ 126,109
Income tax expense	35,352	5,156	53,995	14,557
Net (loss attributable) income available to common stockholders	$ 18,116	$ 4,980	$ 5,140	$ 18,272
Diluted	$ 0.15	$ 0.04	$ 0.04	$ 0.16
Difference between Revenue Guidance in Effect before and after Topic 606 \| ASU 2014-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Revenue		$ (865)		$ (3,229)
Income tax expense		(234)		(875)
Net (loss attributable) income available to common stockholders		$ (631)		$ (2,354)
Diluted		$ (0.01)		$ (0.02)
As Adjusted \| ASU 2014-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Revenue		$ 72,130		$ 122,880
Income tax expense		4,922		13,682
Net (loss attributable) income available to common stockholders		$ 4,349		$ 15,918
Diluted		$ 0.03		$ 0.14

Summary of Significant Accounting Policies - Adjustments made to Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Current portion of deferred revenue	$ 22,108	$ 41,846
Deferred revenue, net of current portion	12,027	29,200
Deferred tax liability, net	385,907	342,382
Retained earnings	$ (258,899)	213,107
Difference between Revenue Guidance in Effect before and after Topic 606 \| ASU 2014-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Current portion of deferred revenue		(7,707)
Deferred revenue, net of current portion		(18,690)
Deferred tax liability, net		7,160
Retained earnings		(19,237)
As Adjusted \| ASU 2014-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Current portion of deferred revenue		34,139
Deferred revenue, net of current portion		10,510
Deferred tax liability, net		349,542
Retained earnings		$ 193,870

- Definition

The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

+ References + Details

- Definition

The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References + Details

Summary of Significant Accounting Policies - Adoption of ASU 2016-16 Effect on Condensed Consolidated Statement of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Income tax expense	$ 35,352	$ 5,156	$ 53,995	$ 14,557
Net loss	(58,690)	(37,054)	(120,074)	(92,506)
Net (loss attributable) income available to common stockholders	$ 18,116	$ 4,980	$ 5,140	$ 18,272
Basic earnings per share	$ 0.16	$ 0.04	$ 0.04	$ 0.16
Diluted earnings per share	$ 0.15	$ 0.04	$ 0.04	$ 0.16
Pre-Adoption Accounting \| ASU 2016-16
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Income tax expense	$ 18,598		$ 24,379
Net loss	(41,936)		(90,458)
Net (loss attributable) income available to common stockholders	$ 34,870		$ 34,756
Basic earnings per share	$ 0.30		$ 0.30
Diluted earnings per share	$ 0.29		$ 0.29
Effect of Adoption \| ASU 2016-16
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Income tax expense	$ 16,754		$ 29,616
Net loss	(16,754)		(29,616)
Net (loss attributable) income available to common stockholders	$ (16,754)		$ (29,616)
Basic earnings per share	$ (0.14)		$ (0.26)
Diluted earnings per share	$ (0.14)		$ (0.25)

Fair Value Measurements - Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Details) - Interest Rate Swaps - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Financial Assets		$ 14,028
Financial Liabilities	$ 4,370	1,280
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Financial Assets		14,028
Financial Liabilities	$ 4,370	$ 1,280

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Realized gain on interest rate swaps			$ 1,279	$ (993)
Interest Expense
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Realized gain on interest rate swaps	$ 22,335	$ 6	22,716	(144)
Other Income
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Realized gain on interest rate swaps	$ 1,990	$ (717)	4,252	$ (993)
2016 Term Loan Facility \| Derivatives Designated as Hedging Instruments \| Interest Expense
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Realized gain on interest rate swaps			22,500
Aggregation Facility \| Derivatives Designated as Hedging Instruments \| Other Income
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Realized gain on interest rate swaps			$ 2,000

Fair Value Measurements - Schedule of Carrying Values and Fair Values of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, Carrying Value	$ 1,142,786	$ 956,107
Long-term debt, Fair Value	1,166,032	995,662
Floating-rate Long-term Debt
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, Carrying Value	481,500	757,044
Long-term debt, Fair Value	481,500	757,044
Fixed-rate Long-term Debt
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, Carrying Value	661,286	199,063
Long-term debt, Fair Value	$ 684,532	$ 238,618

Inventories - Summary of Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Solar energy systems held for sale	$ 12,113	$ 21,971
Photovoltaic installation products	1,022	626
Total inventories	$ 13,135	$ 22,597

Solar Energy Systems (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Property Subject To Or Available For Operating Lease [Line Items]
Solar energy systems, gross	$ 1,916,550	$ 1,773,555
Less: Accumulated depreciation and amortization	(161,124)	(129,640)
Solar energy systems, net excluding inventory	1,755,426	1,643,915
Solar energy system inventory	29,374	29,617
Solar energy systems, net	1,784,800	1,673,532
System Equipment Costs
Property Subject To Or Available For Operating Lease [Line Items]
Solar energy systems, gross	1,540,791	1,437,419
Initial Direct Costs Related to Solar Energy Systems
Property Subject To Or Available For Operating Lease [Line Items]
Solar energy systems, gross	$ 375,759	$ 336,136

Solar Energy Systems - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Property Subject To Or Available For Operating Lease [Line Items]
Depreciation and amortization expense			$ 33,174,000	$ 29,039,000
Solar Energy System Inventory
Property Subject To Or Available For Operating Lease [Line Items]
Depreciation			0
Solar Energy Systems
Property Subject To Or Available For Operating Lease [Line Items]
Depreciation and amortization expense	$ 16,100,000	$ 13,700,000	$ 31,500,000	$ 26,500,000

Property and Equipment - Summary of Property and Equipment Net (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Property, gross	$ 27,819	$ 36,676
Less: Accumulated depreciation and amortization	(15,801)	(21,598)
Property and equipment, net	12,018	15,078
Vehicles Acquired Under Capital Leases
Property Plant And Equipment [Line Items]
Property, gross	11,403	15,113
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property, gross	$ 12,301	15,071
Furniture and Computer and Other Equipment
Property Plant And Equipment [Line Items]
Property and Equipment, Estimated Useful Lives	3 years
Property, gross	$ 4,115	$ 6,492
Minimum \| Vehicles Acquired Under Capital Leases
Property Plant And Equipment [Line Items]
Property and Equipment, Estimated Useful Lives	3 years
Minimum \| Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and Equipment, Estimated Useful Lives	1 year
Maximum \| Vehicles Acquired Under Capital Leases
Property Plant And Equipment [Line Items]
Property and Equipment, Estimated Useful Lives	5 years
Maximum \| Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and Equipment, Estimated Useful Lives	12 years

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Property Plant And Equipment [Line Items]
Depreciation and amortization expense			$ 33,174	$ 29,039
Solar Energy Systems
Property Plant And Equipment [Line Items]
Depreciation and amortization expense	$ 16,100	$ 13,700	31,500	26,500
Property and equipment
Property Plant And Equipment [Line Items]
Depreciation and amortization expense	1,300	2,100	3,000	4,500
Vehicles Acquired Under Capital Leases \| Solar Energy Systems
Property Plant And Equipment [Line Items]
Depreciation and amortization expense	$ 600	$ 900	$ 1,300	$ 2,000

Intangible Assets - Summary of Intangible Assets, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Finite Lived Intangible Assets [Line Items]
Intangible assets, carrying value	$ 2,086	$ 2,201
Intangible assets, accumulated amortization	(1,491)	(1,339)
Total intangible assets, net	595	862
Internal-use software
Finite Lived Intangible Assets [Line Items]
Intangible assets, carrying value	1,199	1,314
Intangible assets, accumulated amortization	(964)	(872)
Developed Technology
Finite Lived Intangible Assets [Line Items]
Intangible assets, carrying value	522	522
Intangible assets, accumulated amortization	(291)	(258)
Trademarks/Trade Names
Finite Lived Intangible Assets [Line Items]
Intangible assets, carrying value	201	201
Intangible assets, accumulated amortization	(89)	(79)
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Intangible assets, carrying value	164	164
Intangible assets, accumulated amortization	$ (147)	$ (130)

Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 130	$ 139	$ 266	$ 279

Accrued Compensation - Summary of Accrued Compensation (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Accrued Compensation Disclosure [Abstract]
Accrued payroll	$ 10,519	$ 13,064
Accrued commissions	7,496	7,928
Total accrued compensation	$ 18,015	$ 20,992

Accrued and Other Current Liabilities - Schedule of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Current portion of lease pass-through financing obligation	$ 4,985	$ 4,931
Accrued unused commitment fees and interest	4,775	7,445
Accrued professional fees	4,338	3,977
Sales, use and property taxes payable	2,967	3,046
Accrued workers' compensation	2,555	1,446
Accrued inventory	1,818	4,122
Workmanship accrual	1,404	1,359
Current portion of deferred rent	927	937
Other accrued expenses	2,321	2,412
Total accrued and other current liabilities	$ 26,090	$ 29,675

Debt Obligations - Schedule of Debt Obligations (Details) - USD ($)

1 Months Ended

6 Months Ended

12 Months Ended

Jun. 30, 2018

Dec. 31, 2017

Derivative Financial Instruments - Schedule of Derivative Financial Instruments at Fair Value (Details) - Interest Rate Swaps - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Derivatives Designated as Hedging Instruments \| Other Noncurrent Liabilities
Derivatives Fair Value [Line Items]
Fair Value	$ 4,370
Derivatives Designated as Hedging Instruments \| Other Noncurrent Assets, Net
Derivatives Fair Value [Line Items]
Fair Value		$ 14,028
Derivatives Not Designated as Hedging Instruments \| Other Noncurrent Liabilities
Derivatives Fair Value [Line Items]
Fair Value		$ 1,280

Redeemable Non-Controlling Interests and Equity - Schedule of Reserved Shares of Common Stock for Issuance (Details) - shares	Jun. 30, 2018	Dec. 31, 2017
Equity [Abstract]
Shares available for grant under equity incentive plans	14,267,000	12,774,000
Restricted stock units issued and outstanding	6,746,000	6,688,000
Stock options issued and outstanding	3,513,000	3,837,000
Long-term incentive plan	2,706,000	2,706,000
Total	27,232,000	26,005,000

Redeemable Non-Controlling Interests and Equity - Schedule of Changes in Redeemable Non-Controlling Interests (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Redeemable Noncontrolling Interest [Line Items]
Balance at beginning of period	$ 122,444
Contributions from redeemable non-controlling interests	64,999
Distributions to redeemable non-controlling interests	(5,112)
Balance at end of period	122,647
Redeemable Non Controlling Interests
Redeemable Noncontrolling Interest [Line Items]
Net loss	$ (59,684)

Redeemable Non-Controlling Interests, Equity and Preferred Stock - Additional Information (Details)	6 Months Ended
	Jun. 30, 2018 USD ($)
Put Option
Redeemable Noncontrolling Interest [Line Items]
Fund options expected to exercise	$ 0
Put Option \| Minimum
Redeemable Noncontrolling Interest [Line Items]
Purchase price for investors' interest in funds under Put Options	2,100,000
Put Option \| Maximum
Redeemable Noncontrolling Interest [Line Items]
Purchase price for investors' interest in funds under Put Options	4,100,000
Call Option
Redeemable Noncontrolling Interest [Line Items]
Fund options expected to exercise	0
Call Option \| Minimum
Redeemable Noncontrolling Interest [Line Items]
Purchase price for investors' interest in funds under Put Options	1,200,000
Call Option \| Maximum
Redeemable Noncontrolling Interest [Line Items]
Purchase price for investors' interest in funds under Put Options	$ 7,000,000

Equity Compensation Plans - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended
	Jan. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grant under equity incentive plans		14,267,000	12,774,000
Unrecognized Stock-Based Compensation Expense		$ 18,858
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized Stock-Based Compensation Expense		$ 1,800
2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grant under equity incentive plans		14,300,000
Number of additional shares available for issuance	4,600,000

Equity Compensation Plans - RSU Activity (Details)	6 Months Ended
Equity Compensation Plans - RSU Activity (Details)	Jun. 30, 2018 $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Awards, Outstanding at December 31, 2017 \| shares	6,688,000
Number of Awards, Granted \| shares	3,183,000
Number of Awards, Vested \| shares	(2,629,000)
Number of Awards, Forfeited \| shares	(496,000)
Number of Awards, Outstanding at March 31, 2018 \| shares	6,746,000
Weighted Average Grant Date Fair Value, Outstanding at December 31, 2017 \| $ / shares	$ 3.20
Weighted Average Grant Date Fair Value, Granted \| $ / shares	3.87
Weighted Average Grant Date Fair Value, Vested \| $ / shares	2.80
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	3.39
Weighted Average Grant Date Fair Value, Outstanding at March 31, 2018 \| $ / shares	$ 3.66

Equity Compensation Plans - Summary of Unrecognized Stock-Based Compensation Expense (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Schedule Of Stock Options [Line Items]
Unrecognized Stock-Based Compensation Expense	$ 18,858
RSUs
Schedule Of Stock Options [Line Items]
Unrecognized Stock-Based Compensation Expense, other than stock options	$ 16,934
Weighted- Average Period of Recognition	1 year 10 months 24 days
Time Based Stock Options
Schedule Of Stock Options [Line Items]
Unrecognized Stock-Based Compensation Expense, stock options	$ 1,924
Weighted- Average Period of Recognition	1 year 8 months 12 days

Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Aug. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Accounts payable—related party		$ 73		$ 73		$ 163
Accrued equity distributions		10,114		10,114		16,437
Related Party
Related Party Transaction [Line Items]
Amounts due from direct-sales personnel		5,300		5,300		6,600
Provision for advances to direct-sales personnel				1,000		1,000
Accrued equity distributions		1,600		1,600		$ 1,200
Vivint Services
Related Party Transaction [Line Items]
Fees incurred in conjunction with agreements entered		$ 4,300	$ 400	$ 5,300	$ 1,100
Initial term of agreement period	2 years

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Apr. 30, 2018	Sep. 30, 2016	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other Commitments [Line Items]
Aggregate operating lease expense			$ 3.8	$ 4.1	$ 7.7	$ 8.4
Standby letter of credit outstanding			13.5		13.5
Total estimated obligation earned over deferment period			$ 7.1		$ 7.1
Sun Edison Inc
Other Commitments [Line Items]
Unsecured claim initial amount		$ 1,000.0
Claim amount received from other party	$ 590.0
Received initial distribution amount	$ 2.1

Subsequent Events - Additional Information (Details) - Subsequent Event	Aug. 03, 2018 USD ($) MW	Jul. 31, 2018 USD ($)
Subsequent Event [Line Items]
Total commitment under investment fund arrangement	$ 410,000,000
Estimated future solar energy system installation \| MW	95
Vivint Solar Asset1 Project Company L L C \| Senior Secured Loan Facility
Subsequent Event [Line Items]
Debt instrument, annual rate plus spread adjustment based on risk premium	1.90%
Debt instrument, frequency of periodic payment	Scheduled principal payments are due on a quarterly basis, at the end of January, April, July and October of each year.
Vivint Solar Asset1 Project Company L L C \| Senior Secured Loan Facility \| Interest Rate Swaps
Subsequent Event [Line Items]
Debt instrument interest rate	1.50%
Financial Institutions Borrower \| Vivint Solar Asset1 Project Company L L C \| Senior Secured Loan Facility \| Maximum
Subsequent Event [Line Items]
Total commitment under investment fund arrangement	$ 130,000,000
Investment Funds
Subsequent Event [Line Items]
Total commitment under investment fund arrangement		$ 50,000,000
Tax Equity Investment Funds \| Vivint Solar Asset1 Owner L L C
Subsequent Event [Line Items]
Total commitment under investment fund arrangement	150,000,000
Cash Equity Investment Funds \| Vivint Solar Asset1 Class B L L C
Subsequent Event [Line Items]
Total commitment under investment fund arrangement	$ 47,000,000

June 30, 2018

Fair Value

Balance Sheet Location

Derivatives designated as hedging instruments:

Interest rate swaps

Other non-current liabilities