First Solar (FSLR) 10-K 22 Feb 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($) $ / shares in Units, $ in Billions	12 Months Ended
	Dec. 31, 2018	Feb. 15, 2019	Jun. 30, 2018
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Registrant Name	FIRST SOLAR, INC.
Entity Central Index Key	1,274,494
Entity Well Known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Public Float			$ 4.3
Entity Common Stock, Shares Outstanding		104,894,572
Entity Par Value Per Share	$ 0.001

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 1,403,562	$ 2,268,534
Marketable securities	1,143,704	720,379
Accounts receivable trade, net	128,282	211,797
Accounts receivable, unbilled and retainage	458,166	174,608
Inventories	387,912	172,370
Balance of systems parts	56,906	28,840
Project assets	37,930	77,931
Notes receivable, affiliate	0	20,411
Prepaid expenses and other current assets	243,061	157,902
Total current assets	3,859,523	3,832,772
Property, plant and equipment, net	1,756,211	1,154,537
PV solar power systems, net	308,640	417,108
Project assets	460,499	424,786
Deferred tax assets, net	77,682	51,417
Restricted cash and investments	318,390	424,783
Equity Method Investments	3,186	217,230
Goodwill	14,462	14,462
Intangible assets, net	74,162	80,227
Inventories	130,083	113,277
Notes receivable, affiliates	22,832	48,370
Other assets	95,692	85,532
Total assets	7,121,362	6,864,501
Current liabilities:
Accounts payable	233,287	120,220
Income taxes payable	20,885	19,581
Accrued expenses	441,580	366,827
Current portion of long-term debt	5,570	13,075
Deferred revenue	129,755	81,816
Other current liabilities	14,380	48,757
Total current liabilities	845,457	650,276
Accrued solar module collection and recycling liability	134,442	166,609
Long-term debt	461,221	380,465
Other liabilities	467,839	568,454
Total liabilities	1,908,959	1,765,804
Commitments and contingencies
Stockholders' equity:
Common stock, $0.001 par value per share; 500,000,000 shares authorized; 104,885,261 and 104,468,460 shares issued and outstanding at December 31, 2018 and 2017, respectively	105	104
Additional paid-in capital	2,825,211	2,799,107
Accumulated earnings	2,441,553	2,297,227
Accumulated other comprehensive (loss) income	(54,466)	2,259
Total stockholders' equity	5,212,403	5,098,697
Total liabilities and stockholders' equity	$ 7,121,362	$ 6,864,501

Consolidated Balance Sheets Con

Consolidated Balance Sheets Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Common Stock, Par Value	$ 0.001	$ 0.001
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Shares Issued	104,885,261	104,468,460
Common Stock, Shares Outstanding	104,885,261	104,468,460

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net sales	$ 2,244,044	$ 2,941,324	$ 2,904,563
Cost of sales	1,851,867	2,392,377	2,266,145
Gross profit	392,177	548,947	638,418
Operating expenses:
Selling, general and administrative	176,857	202,699	261,994
Research and development	84,472	88,573	124,762
Production start-up	90,735	42,643	1,021
Restructuring and asset impairments	0	37,181	743,862
Goodwill impairment	0	0	74,930
Total operating expenses	352,064	371,096	1,206,569
Operating income (loss)	40,113	177,851	(568,151)
Foreign currency loss, net	(570)	(9,640)	(14,007)
Interest income	59,788	35,704	25,193
Interest expense, net	(25,921)	(25,765)	(20,538)
Other income, net	39,737	23,965	40,252
Income (loss) before taxes and equity in earnings	113,147	202,115	(537,251)
Income tax expense	(3,441)	(371,996)	(23,167)
Equity in earnings, net of tax	34,620	4,266	144,306
Net income (loss)	$ 144,326	$ (165,615)	$ (416,112)
Net income (loss) per share:
Basic	$ 1.38	$ (1.59)	$ (4.05)
Diluted	$ 1.36	$ (1.59)	$ (4.05)
Weighted-average number of shares used in per share calculations:
Basic	104,745	104,328	102,866
Diluted	106,113	104,328	102,866

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net income (loss)	$ 144,326	$ (165,615)	$ (416,112)
Foreign currency translation adjustments	(1,034)	11,832	(7,409)
Unrealized (loss) gain on marketable securities and restricted investments, net of tax of $3,735, $(588), and $2,518	(57,747)	3,217	(21,713)
Unrealized gain (loss) on derivative instruments, net of tax of $(996), $1,396, and $(691)	2,056	(2,883)	3,735
Other comprehensive (loss) income	(56,725)	12,166	(25,387)
Comprehensive income (loss)	87,601	(153,449)	(441,499)
Other comprehensive (loss) income, unrealized (loss) gain on marketable securities and restricted investments, tax	3,735	(588)	2,518
Other comprehensive (loss) income, unrealized gain (loss) on derivative instruments, tax	$ (996)	$ 1,396	$ (691)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative-effect adjustment for the adoption of new accounting standard | Accounting Standards Update 2016-09	$ 27,454		$ 2,420	$ 25,034
Common stock, shares at Dec. 31, 2015		101,767,000
Stockholders' equity, beginning balance at Dec. 31, 2015	5,618,396	$ 102	2,748,894	2,853,920	$ 15,480
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(416,112)			(416,112)
Other comprehensive (loss) income	(25,387)				(25,387)
Common stock issued for share-based compensation, shares		2,574,000
Common stock issued for share-based compensation	6,320	$ 2	6,318
Tax withholding related to vesting of restricted stock, shares		(306,000)
Tax withholding related to vesting of restricted stock	(20,407)	$ 0	(20,407)
Share-based compensation expense	28,085		28,085
Common stock, shares at Dec. 31, 2016		104,035,000
Stockholders' equity, ending balance at Dec. 31, 2016	5,218,349	$ 104	2,765,310	2,462,842	(9,907)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(165,615)			(165,615)
Other comprehensive (loss) income	12,166				12,166
Common stock issued for share-based compensation, shares		580,000
Common stock issued for share-based compensation	4,474	$ 0	4,474
Tax withholding related to vesting of restricted stock, shares		(147,000)
Tax withholding related to vesting of restricted stock	(5,137)	$ 0	(5,137)
Share-based compensation expense	$ 34,460		34,460
Common stock, shares at Dec. 31, 2017	104,468,460	104,468,000
Stockholders' equity, ending balance at Dec. 31, 2017	$ 5,098,697	$ 104	2,799,107	2,297,227	2,259
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	144,326			144,326
Other comprehensive (loss) income	(56,725)				(56,725)
Common stock issued for share-based compensation, shares		588,000
Common stock issued for share-based compensation	3,426	$ 1	3,425
Tax withholding related to vesting of restricted stock, shares		(171,000)
Tax withholding related to vesting of restricted stock	(11,175)	$ 0	(11,175)
Share-based compensation expense	$ 33,854		33,854
Common stock, shares at Dec. 31, 2018	104,885,261	104,885,000
Stockholders' equity, ending balance at Dec. 31, 2018	$ 5,212,403	$ 105	$ 2,825,211	$ 2,441,553	$ (54,466)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income (loss)	$ 144,326	$ (165,615)	$ (416,112)
Adjustments to reconcile net income (loss) to cash (used in) provided by operating activities:
Depreciation, amortization and accretion	130,736	115,313	230,940
Impairments and net losses on disposal of long-lived assets	8,065	35,364	838,467
Share-based compensation	34,154	35,121	28,712
Equity in earnings, net of tax	(34,620)	(4,266)	(144,306)
Distributions received from equity method investments	12,394	23,042	18,562
Remeasurement of monetary assets and liabilities	8,740	(15,823)	5,442
Deferred income taxes	(10,112)	173,368	90,555
Gains on sales of marketable securities and restricted investments	(55,405)	(49)	(41,632)
Noncash consideration from the sale of systems	0	0	(20,091)
Liabilities assumed by customers for the sale of systems	(240,865)	(24,203)	0
Other, net	2,121	2,339	13,863
Changes in operating assets and liabilities
Accounts receivable, trade, unbilled and retainage	(202,298)	85,760	178,894
Prepaid expenses and other current assets	(53,488)	26,680	9,269
Inventories and balance of systems parts	(257,229)	212,758	95,785
Project assets and PV solar power systems	49,939	981,273	(571,655)
Other assets	(11,920)	(1,269)	(19,245)
Income tax receivable and payable	(49,169)	169,079	(61,383)
Accounts payable	96,443	(47,191)	(191,642)
Accrued expenses and other liabilities	132,382	(258,028)	158,693
Accrued solar module collection and recycling liability	(31,003)	(2,976)	3,637
Net cash (used in) provided by operating activities	(326,809)	1,340,677	206,753
Cash flows from investing activities:
Purchases of property, plant and equipment	(739,838)	(514,357)	(229,452)
Purchases of marketable securities and restricted investments	(1,369,036)	(580,971)	(422,609)
Proceeds from sales and maturities of marketable securities and restricted investments	1,135,984	466,309	525,515
Proceeds from sales of equity method investments	247,595	0	291,502
Payments received on notes receivable, affiliates	48,729	1,740	3,053
Other investing activities	(6,148)	477	(23,489)
Net cash (used in) provided by investing activities	(682,714)	(626,802)	144,520
Cash flows from financing activities:
Repayment of borrowings under revolving credit facility	0	0	(550,000)
Proceeds from borrowings under revolving credit facility	0	0	550,000
Repayment of long-term debt	(18,937)	(24,078)	(137,367)
Proceeds from borrowings under long-term debt, net of discounts and issuance costs	290,925	215,415	26,816
Payments of tax withholdings for restricted shares	(11,175)	(5,137)	(20,407)
Proceeds from commercial letters of credit	0	43,025	0
Contingent consideration payments and other financing activities	(5,585)	(37,180)	(5,435)
Net cash provided by (used in) financing activities	255,228	192,045	(136,393)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(13,558)	8,866	(6,306)
Net (decrease) increase in cash, cash equivalents and restricted cash	(767,853)	914,786	208,574
Cash, cash equivalents and restricted cash, beginning of the period	2,330,476	1,415,690	1,207,116
Cash, cash equivalents and restricted cash, end of the period	1,562,623	2,330,476	1,415,690
Supplemental disclosure of noncash investing and financing activities:
Property, plant and equipment acquisitions funded by liabilities	138,270	164,946	28,687
Sale of system previously accounted for as sale-leaseback financing	31,992	0	0
Acquisitions currently or previously funded by liabilities and contingent consideration	2,915	9,315	30,092
Accrued interest capitalized to long-term debt	3,512	18,401	0
Sale of equity method investment funded by note receivable, affiliate	$ 0	$ 0	$ 50,000

Note 1. First Solar and Its Bus

Note 1. First Solar and Its Business (Notes)	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
First Solar and Its Business	1. First Solar and Its Business We are a leading global provider of comprehensive PV solar energy solutions. We design, manufacture, and sell PV solar modules with an advanced thin film semiconductor technology and also develop, design, construct, and sell PV solar power systems that primarily use the modules we manufacture. Additionally, we provide O&M services to system owners. We have substantial, ongoing R&D efforts focused on module and system-level innovations. We are the world’s largest thin film PV solar module manufacturer and one of the world’s largest PV solar module manufacturers.

Note 2. Summary of Significant

Note 2. Summary of Significant Accounting Policies (Notes)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation. These consolidated financial statements include the accounts of First Solar, Inc. and its subsidiaries and are prepared in accordance with U.S. GAAP. We eliminated all intercompany transactions and balances during consolidation. Certain prior year balances were reclassified to conform to the current year presentation. Use of Estimates. The preparation of consolidated financial statements in conformity with U.S. GAAP requires us to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and the accompanying notes. On an ongoing basis, we evaluate our estimates, including those related to inputs used to recognize revenue over time, accrued solar module collection and recycling liabilities, product warranties, accounting for income taxes, long-lived asset impairments, and testing goodwill. Despite our intention to establish accurate estimates and reasonable assumptions, actual results could differ materially from such estimates and assumptions. Fair Value Measurements. We measure certain assets and liabilities at fair value, which is defined as the price that would be received from the sale of an asset or paid to transfer a liability (i.e., an exit price) on the measurement date in an orderly transaction between market participants in the principal or most advantageous market for the asset or liability. Our fair value measurements use the following hierarchy, which prioritizes valuation inputs based on the extent to which the inputs are observable in the market. • Level 1 – Valuation techniques in which all significant inputs are unadjusted quoted prices from active markets for assets or liabilities that are identical to the assets or liabilities being measured. • Level 2 – Valuation techniques in which significant inputs include quoted prices from active markets for assets or liabilities that are similar to the assets or liabilities being measured and/or quoted prices for assets or liabilities that are identical or similar to the assets or liabilities being measured from markets that are not active. Also, model-derived valuations in which all significant inputs are observable in active markets are Level 2 valuation techniques. • Level 3 – Valuation techniques in which one or more significant inputs are unobservable. Such inputs reflect our estimate of assumptions that market participants would use to price an asset or liability. Cash and Cash Equivalents. We consider highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents with the exception of time deposits, which are presented as marketable securities. Restricted Cash . Restricted cash consists of cash and cash equivalents held by various banks to secure certain of our letters of credit and other such deposits designated for the construction or operation of systems projects as well as the payment of amounts related to project specific debt financings. Restricted cash also includes cash and cash equivalents held in custodial accounts to fund the estimated future costs of our solar module collection and recycling obligations. Restricted cash for our letters of credit is classified as current or noncurrent based on the maturity date of the corresponding letter of credit. Restricted cash for project construction, operation, and financing is classified as current or noncurrent based on the intended use of the restricted funds. Restricted cash held in custodial accounts is classified as noncurrent to align with the nature of the corresponding collection and recycling liabilities. Marketable Securities and Restricted Investments. We determine the classification of our marketable securities and restricted investments at the time of purchase and reevaluate such designation at each balance sheet date. As of December 31, 2018 and 2017 , all of our marketable securities and restricted investments were classified as available-for-sale debt securities. Accordingly, we record them at fair value and account for the net unrealized gains and losses as part of “ Accumulated other comprehensive (loss) income ” until realized. We record realized gains and losses on the sale of our marketable securities and restricted investments in “ Other income, net ” computed using the specific identification method. We may sell marketable securities prior to their stated maturities after consideration of our liquidity requirements. We view unrestricted securities with maturities beyond 12 months as available to support our current operations and, accordingly, classify such securities as current assets under “ Marketable securities ” in the consolidated balance sheets. Restricted investments consist of long-term duration marketable securities that we hold in custodial accounts to fund the estimated future costs of our solar module collection and recycling obligations. Accordingly, we classify restricted investments as noncurrent assets under “ Restricted cash and investments ” in the consolidated balance sheets. All of our available-for-sale marketable securities and restricted investments are subject to a periodic impairment review. We consider a marketable security or restricted investment to be impaired when its fair value is less than its cost basis, in which case we would further review the security or investment to determine if it is other-than-temporarily impaired. In performing such an evaluation, we review factors such as the length of time and the extent to which its fair value has been below its cost basis, the financial condition of the issuer and any changes thereto, our intent to sell, and whether it is more likely than not that we will be required to sell the marketable security or restricted investment before we have recovered its cost basis. If a marketable security or restricted investment were other-than-temporarily impaired, we write it down through “ Other income, net ” to its impaired value and establish that value as its new cost basis. Accounts Receivable Trade and Allowance for Doubtful Accounts . We record trade accounts receivable for our unconditional rights to consideration arising from our performance under contracts with customers. The carrying value of such receivables, net of the allowance for doubtful accounts, represents their estimated net realizable value. We estimate our allowance for doubtful accounts for specific trade receivable balances based on historical collection trends, the age of outstanding trade receivables, existing economic conditions, and the financial security, if any, associated with the receivables. Past-due trade receivable balances are written off when our internal collection efforts have been unsuccessful. Our module and other equipment sales generally include up to 45-day payment terms following the transfer of control of the products to the customer. In addition, certain module and equipment sale agreements may require a down payment for a portion of the transaction price upon or shortly after entering into the agreement or related purchase order. Payment terms for sales of our solar power systems, EPC services, and operations and maintenance services vary by contract but are generally due upon demand or within several months of satisfying the associated performance obligations. As a practical expedient, we do not adjust the promised amount of consideration for the effects of a significant financing component when we expect, at contract inception, that the period between our transfer of a promised product or service to a customer and when the customer pays for that product or service will be one year or less. We typically do not include extended payment terms in our contracts with customers. Accounts Receivable, Unbilled . Accounts receivable, unbilled represents a contract asset for revenue that has been recognized in advance of billing the customer, which is common for long-term construction contracts. For example, we typically recognize revenue from contracts for the construction and sale of PV solar power systems over time using cost based input methods, which recognize revenue and gross profit as work is performed based on the relationship between actual costs incurred compared to the total estimated costs of the contract. Accordingly, revenue could be recognized in advance of billing the customer, resulting in an amount recorded to “ Accounts receivable, unbilled and retainage .” Once we have an unconditional right to consideration under a construction contract, we typically bill our customer and reclassify the “ Accounts receivable, unbilled and retainage ” to “ Accounts receivable trade, net .” Billing requirements vary by contract but are generally structured around the completion of certain construction milestones. We assess our unbilled accounts receivable for impairment in accordance with the allowance for doubtful accounts policy described above. Retainage. Certain of our EPC contracts for PV solar power systems we build contain retainage provisions. Retainage represents a contract asset for the portion of the contract price earned by us for work performed, but held for payment by the customer as a form of security until we reach certain construction milestones. We consider whether collectibility of such retainage is reasonably assured in connection with our overall assessment of the collectibility of amounts due or that will become due under our EPC contracts. Retainage included within “ Accounts receivable, unbilled and retainage ” is expected to be billed and collected within the next 12 months. After we satisfy the EPC contract requirements and have an unconditional right to consideration, we typically bill for retainage and reclassify such amounts to “ Accounts receivable trade, net .” Inventories – Current and Noncurrent. We report our inventories at the lower of cost or net realizable value. We determine cost on a first-in, first-out basis and include both the costs of acquisition and the costs of manufacturing in our inventory costs. These costs include direct materials, direct labor, and indirect manufacturing costs, including depreciation and amortization. Our capitalization of costs into inventory is based on the normal utilization of our plants. If our plant utilization is abnormally low, the portion of our indirect manufacturing costs related to the abnormal utilization level is expensed as incurred. Other abnormal manufacturing costs, such as wasted materials or excess yield losses, are also expensed as incurred. Finished goods inventory is comprised exclusively of solar modules that have not yet been installed in a PV solar power plant under construction or sold to a third-party customer. As needed, we may purchase a critical raw material that is used in our core production process in quantities that exceed anticipated consumption within our normal operating cycle (which is 12 months). We classify such raw materials that we do not expect to consume within our normal operating cycle as noncurrent. We regularly review the cost of inventories, including noncurrent inventories, against their estimated net realizable value and record write-downs if any inventories have costs in excess of their net realizable values. We also regularly evaluate the quantities and values of our inventories, including noncurrent inventories, in light of current market conditions and trends, among other factors, and record write-downs for any quantities in excess of demand or for any obsolescence. This evaluation considers the use of modules in our systems business, expected demand, anticipated sales prices, strategic raw material requirements, new product development schedules, product obsolescence, product merchantability, and other factors. Market conditions are subject to change, and actual consumption of our inventory could differ from forecasted demand. Balance of Systems Parts. BoS parts represent mounting, electrical, and other construction parts purchased for PV solar power systems to be constructed or currently under construction, which are not yet installed in a system. These construction parts include items such as posts, tilt brackets, tables, harnesses, combiner boxes, inverters, cables, tracker equipment, and other parts that we may purchase or assemble for the systems we construct. We carry these parts at the lower of cost or net realizable value and determine our BoS costs on a weighted-average basis. BoS parts do not include any solar modules that we manufacture. Property, Plant and Equipment. We report our property, plant and equipment at cost, less accumulated depreciation. Cost includes the price paid to acquire or construct the assets, required installation costs, interest capitalized during the construction period, and any expenditures that substantially add to the value of or substantially extend the useful life of the assets. We capitalize costs related to computer software obtained or developed for internal use, which generally includes enterprise-level business and finance software that we customize to meet our specific operational requirements. We expense repair and maintenance costs at the time we incur them. We begin depreciation for our property, plant and equipment when they are placed in service. We consider such assets to be placed in service when they are both in the location and condition for their intended use. We compute depreciation expense using the straight-line method over the estimated useful lives of assets, as presented in the table below. We depreciate leasehold improvements over the shorter of their estimated useful lives or the remaining term of the lease. The estimated useful life of an asset is reassessed whenever applicable facts and circumstances indicate a change in the estimated useful life of such asset has occurred. Useful Lives in Years Buildings and building improvements 25 – 40 Manufacturing machinery and equipment 5 – 10 Furniture, fixtures, computer hardware, and computer software 3 – 7 Leasehold improvements up to 15 PV Solar Power Systems. PV solar power systems represent project assets that we may temporarily own and operate after being placed in service. We report our PV solar power systems at cost, less accumulated depreciation. When we are entitled to incentive tax credits for our systems, we reduce the related carrying value of the assets by the amount of the tax credits, which reduces future depreciation. We begin depreciation for PV solar power systems when they are placed in service. We compute depreciation expense for the systems using the straight-line method over the shorter of the term of the related PPA or 25 years. Accordingly, our current PV solar power systems have estimated useful lives ranging from 19 to 25 years. Project Assets. Project assets primarily consist of costs related to solar power projects in various stages of development that are capitalized prior to the completion of the sale of the project, including projects that may have begun commercial operation under PPAs and are actively marketed and intended to be sold. These project related costs include costs for land, development, and construction of a PV solar power system. Development costs may include legal, consulting, permitting, transmission upgrade, interconnection, and other similar costs. We typically classify project assets as noncurrent due to the nature of solar power projects (long-lived assets) and the time required to complete all activities to develop, construct, and sell projects, which is typically longer than 12 months. Once we enter into a definitive sales agreement, we classify such project assets as current until the sale is completed and we have met all of the criteria to recognize the sale as revenue. Any income generated by a project while it remains within project assets is accounted for as a reduction to our basis in the project. If a project is completed and begins commercial operation prior to the closing of a sales arrangement, the completed project will remain in project assets until placed in service. We present all expenditures related to the development and construction of project assets, whether fully or partially owned, as a component of cash flows from operating activities. We review project assets for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. We consider a project commercially viable or recoverable if it is anticipated to be sold for a profit once it is either fully developed or fully constructed. We consider a partially developed or partially constructed project commercially viable or recoverable if the anticipated selling price is higher than the carrying value of the related project assets. We examine a number of factors to determine if the project is expected to be recoverable, including whether there are any changes in environmental, permitting, market pricing, regulatory, or other conditions that may impact the project. Such changes could cause the costs of the project to increase or the selling price of the project to decrease. If a project is not considered recoverable, we impair the respective project assets and adjust the carrying value to the estimated fair value, with the resulting impairment recorded within “Selling, general and administrative” expense. Interest Capitalization . We capitalize interest as part of the historical cost of acquiring or constructing certain assets, including property, plant and equipment; project assets; and PV solar power systems. Interest capitalized for property, plant and equipment or PV solar power systems is depreciated over the estimated useful life of the related assets when they are placed in service. We charge interest capitalized for project assets to cost of sales when such assets are sold and we have met all revenue recognition criteria. We capitalize interest to the extent that interest cost has been incurred and payments have been made to acquire, construct, or develop an asset. We cease capitalization of interest for assets in development or under construction if the assets are substantially complete or if we have sold such assets. Asset Impairments. We assess long-lived assets classified as “held and used,” including our property, plant and equipment; project assets; PV solar power systems; and intangible assets for impairment whenever events or changes in circumstances arise, including consideration of technological obsolescence, that may indicate that the carrying amount of such assets may not be recoverable. These events and changes in circumstances may include a significant decrease in the market price of a long-lived asset; a significant adverse change in the extent or manner in which a long-lived asset is being used or in its physical condition; a significant adverse change in the business climate that could affect the value of a long-lived asset; an accumulation of costs significantly in excess of the amount originally expected for the acquisition or construction of a long-lived asset; a current-period operating or cash flow loss combined with a history of such losses or a projection of future losses associated with the use of a long-lived asset; or a current expectation that, more likely than not, a long-lived asset will be sold or otherwise disposed of significantly before the end of its previously estimated useful life. For purposes of recognition and measurement of an impairment loss, long-lived assets are grouped with other assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. When impairment indicators are present, we compare undiscounted future cash flows, including the eventual disposition of the asset group at market value, to the asset group’s carrying value to determine if the asset group is recoverable. If the carrying value of the asset group exceeds the undiscounted future cash flows, we measure any impairment by comparing the fair value of the asset group to its carrying value. Fair value is generally determined by considering (i) internally developed discounted cash flows for the asset group, (ii) third-party valuations, and/or (iii) information available regarding the current market value for such assets. If the fair value of an asset group is determined to be less than its carrying value, an impairment in the amount of the difference is recorded in the period that the impairment indicator occurs. Estimating future cash flows requires significant judgment, and such projections may vary from the cash flows eventually realized. We consider a long-lived asset to be abandoned after we have ceased use of such asset and we have no intent to use or repurpose the asset in the future. Abandoned long-lived assets are recorded at their salvage value, if any. We classify long-lived assets we plan to sell, excluding project assets and PV solar power systems, as held for sale on our consolidated balance sheets only after certain criteria have been met including: (i) management has the authority and commits to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and the plan to sell the asset have been initiated, (iv) the sale of the asset is probable within 12 months, (v) the asset is being actively marketed at a reasonable sales price relative to its current fair value, and (vi) it is unlikely that the plan to sell will be withdrawn or that significant changes to the plan will be made. We record assets held for sale at the lower of their carrying value or fair value less costs to sell. If, due to unanticipated circumstances, such assets are not sold in the 12 months after being classified as held for sale, then held for sale classification will continue as long as the above criteria are still met. Ventures and Variable Interest Entities. In the normal course of business, we establish wholly owned project companies which may be considered variable interest entities (“VIEs”). We consolidate wholly owned VIEs when we are considered the primary beneficiary of such entities. Additionally, we have, and may in the future form, joint venture type arrangements, including partnerships and partially owned limited liability companies or similar legal structures, with one or more third parties primarily to develop, construct, own, and/or sell solar power projects. We analyze all of our ventures and classify them into two groups: (i) ventures that must be consolidated because they are either not VIEs and we hold a majority voting interest, or because they are VIEs and we are the primary beneficiary and (ii) ventures that do not need to be consolidated because they are either not VIEs and we hold a minority voting interest, or because they are VIEs and we are not the primary beneficiary. Ventures are considered VIEs if (i) the total equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support; (ii) as a group, the holders of the equity investment at risk lack the ability to make certain decisions, the obligation to absorb expected losses, or the right to receive expected residual returns; or (iii) an equity investor has voting rights that are disproportionate to its economic interest and substantially all of the entity’s activities are conducted on behalf of that investor. Our venture agreements typically require us to fund some form of capital for the development and construction of a project, depending upon the opportunity and the market in which our ventures are located. We are considered the primary beneficiary of and are required to consolidate a VIE if we have the power to direct the activities that most significantly impact the VIE’s economic performance and the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the entity. If we determine that we do not have the power to direct the activities that most significantly impact the entity, then we are not the primary beneficiary of the VIE. Equity Method Investments. We use the equity method of accounting for our investments when we have the ability to significantly influence, but not control, the operations or financial activities of the investee. As part of this evaluation, we consider our participating and protective rights in the venture as well as its legal form. We record our equity method investments at cost and subsequently adjust their carrying amount each period for our share of the earnings or losses of the investee and other adjustments required by the equity method of accounting. Distributions received from our equity method investments are recorded as reductions in the carrying value of such investments and are classified on the consolidated statements of cash flows pursuant to the cumulative earnings approach. Under this approach, distributions received are considered returns on investment and are classified as cash inflows from operating activities unless our cumulative distributions received, less distributions received in prior periods that were determined to be returns of investment, exceed our cumulative equity in earnings recognized from the investment. When such an excess occurs, the current period distributions up to this excess are considered returns of investment and are classified as cash inflows from investing activities. We monitor equity method investments for impairment and record reductions in their carrying values if the carrying amount of an investment exceeds its fair value. An impairment charge is recorded when such impairment is deemed to be other-than-temporary. To determine whether an impairment is other-than-temporary, we consider our ability and intent to hold the investment until the carrying amount is fully recovered. Circumstances that indicate an other-than-temporary impairment may have occurred include factors such as decreases in quoted market prices or declines in the operations of the investee. The evaluation of an investment for potential impairment requires us to exercise significant judgment and to make certain assumptions. The use of different judgments and assumptions could result in different conclusions. We recorded impairment losses related to our equity method investments of $3.5 million , $2.0 million , and $0.6 million , net of tax, during the years ended December 31, 2018 , 2017 , and 2016 , respectively. Goodwill. Goodwill represents the excess of the purchase price of acquired businesses over the estimated fair value assigned to the individual assets acquired and liabilities assumed. We do not amortize goodwill, but instead are required to test goodwill for impairment at least annually. We perform impairment tests between the scheduled annual test in the fourth quarter if facts and circumstances indicate that it is more likely than not that the fair value of a reporting unit that has goodwill is less than its carrying value. We may first make a qualitative assessment of whether it is more likely than not that a reporting unit’s fair value is less than its carrying value to determine whether it is necessary to perform a quantitative goodwill impairment test. Such qualitative impairment test considers various factors, including macroeconomic conditions, industry and market considerations, cost factors, the overall financial performance of a reporting unit, and any other relevant events affecting our company or a reporting unit. If we determine through the qualitative assessment that a reporting unit’s fair value is more likely than not greater than its carrying value, the quantitative impairment test is not required. If the qualitative assessment indicates it is more likely than not that a reporting unit’s fair value is less than its carrying value, we perform a quantitative impairment test. We may also elect to proceed directly to the quantitative impairment test without considering qualitative factors. The quantitative impairment test is the comparison of the fair value of a reporting unit with its carrying amount, including goodwill. Our reporting units consist of our modules business and our fully integrated systems business. We define the fair value of a reporting unit as the price that would be received to sell the unit as a whole in an orderly transaction between market participants at the measurement date. We primarily use an income approach to estimate the fair value of our reporting units. Significant judgment is required when estimating the fair value of a reporting unit, including the forecasting of future operating results and the selection of discount and expected future growth rates used to determine projected cash flows. If the estimated fair value of a reporting unit exceeds its carrying value, goodwill is not impaired, and no further analysis is required. Conversely, if the carrying value of a reporting unit exceeds its estimated fair value, we record an impairment loss equal to the excess, not to exceed the total amount of goodwill allocated to the reporting unit. Intangible Assets. Intangible assets primarily include developed technologies or in-process research and development (“IPR&D”) from prior business acquisitions, certain PPAs acquired after the associated PV solar power systems were placed in service, and our internally-generated intangible assets, substantially all of which were patents on technologies related to our products and production processes. We record an asset for patents after the patent has been issued based on the legal, filing, and other costs incurred to secure it. IPR&D is initially capitalized at fair value as an intangible asset with an indefinite life and periodically assessed for impairment. When the IPR&D project is complete, it is reclassified as a definite-lived intangible asset. We amortize intangible assets on a straight-line basis over their estimated useful lives, which generally range from 10 to 20 years. Deferred Revenue. When we receive consideration, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a sales contract, we record deferred revenue, which represents a contract liability. We recognize deferred revenue as net sales after we have transferred control of the goods or services to the customer and all revenue recognition criteria are met. As a practical expedient, we do not adjust the consideration in a contract for the effects of a significant financing component when we expect, at contract inception, that the period between a customer’s down payment and our transfer of a promised product or service to the customer will be one year or less. Additionally, we do not adjust the consideration in a contract for the effects of a significant financing component when the consideration is received as a form of performance security. Product Warranties. We provide a limited PV solar module warranty covering defects in materials and workmanship under normal use and service conditions for approximately 10 years. We also typically warrant that modules installed in accordance with agreed-upon specifications will produce at least 98% of their labeled power output rating during the first year, with the warranty coverage reducing by 0.5% every year thereafter throughout the approximate 25-year limited power output warranty period. In resolving claims under both the limited defect and power output warranties, we typically have the option of either repairing or replacing the covered modules or, under the limited power output warranty, providing additional modules to remedy the power shortfall. Our limited module warranties also include an option for us to remedy claims under such warranties, generally exercisable only after the second year of the warranty period, by making certain cash payments. Under the limited workmanship warranty, the optional cash payment will be equal to the original purchase price of the module, reduced by a degradation factor, and under the limited power output warranty, the cash payment will be equal to the shortfall in power output. Such limited module warranties are standard for module sales and may be transferred from the original purchasers of the solar modules to subsequent purchasers upon resale. As an alternative form of our standard limited module power output warranty, we also offer an aggregated or system-level limited module performance warranty. This system-level limited module performance warranty is designed for utility-scale systems and provides 25 -year system-level ener

Note 3. Recent Accounting Prono

Note 3. Recent Accounting Pronouncements (Notes)	12 Months Ended
	Dec. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	3. Recent Accounting Pronouncements In February 2018, the Financial Accounting Standard Board (“FASB”) issued ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220) – Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, to allow entities to reclassify the income tax effects of the Tax Act on items within accumulated other comprehensive income to retained earnings. The adoption of ASU 2018-02 in the fourth quarter of 2018 did not have a significant impact on our consolidated financial statements and associated disclosures as we did not elect to reclassify the income tax effects of the Tax Act from accumulated other comprehensive income to retained earnings. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815) – Targeted Improvements to Accounting for Hedging Activities , to simplify certain aspects of hedge accounting for both non-financial and financial risks and better align the recognition and measurement of hedge results with an entity’s risk management activities. ASU 2017-12 also amends certain presentation and disclosure requirements for hedging activities and changes how an entity assesses hedge effectiveness. ASU 2017-12 is effective for fiscal years and interim periods within those years beginning after December 15, 2018, and early adoption is permitted. We are currently evaluating the impact ASU 2017-12 will have on our consolidated financial statements and associated disclosures. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 230) – Intra-Entity Transfers of Assets Other Than Inventory . ASU 2016-16 requires the recognition of income tax consequences of intra-entity transfers of assets, other than inventory, when the transfer occurs. Two common examples of assets included in the scope of ASU 2016-16 are intellectual property and long-lived assets. The adoption of ASU 2016-16 in the first quarter of 2018 did not have a significant impact on our consolidated financial statements and associated disclosures. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326) , to provide financial statement users with more useful information about expected credit losses. ASU 2016-13 also changes how entities measure credit losses on financial instruments and the timing of when such losses are recorded. ASU 2016-13 is effective for fiscal years and interim periods within those years beginning after December 15, 2019, and early adoption is permitted for periods beginning after December 15, 2018. We are currently evaluating the impact ASU 2016-13 will have on our consolidated financial statements and associated disclosures. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , to increase transparency and comparability among organizations by recognizing a right-of-use asset and a lease liability on the balance sheet for all leases with terms longer than 12 months and disclosing key information about leasing transactions. Leases will be classified as either operating or financing, with such classification affecting the pattern of expense recognition in the income statement. ASU 2016-02 is effective for fiscal years and interim periods within those years beginning after December 15, 2018, and early adoption is permitted. In July 2018, the FASB issued ASU 2018-11, Leases (Topic 842) – Targeted Improvements , which provided an optional transition method to apply the new lease requirements through a cumulative-effect adjustment in the period of adoption. We expect to adopt ASU 2016-02 in the first quarter of 2019 using this optional transition method. We also expect to elect certain practical expedients permitted under the transition guidance, which, among other things, allow us to not reassess prior conclusions related to contracts containing leases or lease classification. We are currently evaluating the impact ASU 2016-02 will have on our consolidated financial statements and associated disclosures and designing the related processes and internal controls. We expect the adoption to have a significant impact on our consolidated balance sheet through the recognition of right-of-use assets and lease liabilities primarily related to real estate arrangements, but do not expect the adoption to have a significant impact on our results of operations or cash flows.

Note 4. Restructuring and Asset

Note 4. Restructuring and Asset Impairments (Notes)	12 Months Ended
	Dec. 31, 2018
Restructuring and Related Activities [Abstract]
Restructuring and Asset Impairments	4. Restructuring and Asset Impairments Cadmium Telluride Module Manufacturing and Corporate Restructuring In November 2016, our board of directors approved a set of initiatives intended to accelerate our transition to Series 6 module manufacturing and restructure our operations to reduce costs and better align the organization with our long-term strategic plans. Accordingly, we expect to upgrade and replace our legacy manufacturing fleet over the next several years with Series 6 manufacturing equipment, thereby enabling the production of solar modules with a larger form factor, better product attributes, and a lower cost structure. As part of these initiatives, we incurred net charges of $41.8 million during the year ended December 31, 2017 , which included (i) $27.6 million of charges, primarily related to net losses on the disposition of previously impaired Series 4 and Series 5 manufacturing equipment, (ii) $7.6 million of severance benefits to terminated employees, and (iii) $6.7 million of net miscellaneous charges, primarily related to contract terminations, the write-off of operating supplies, and other Series 4 manufacturing exit costs. The commencement of this operational transition in November 2016 represented an expectation that certain of our module manufacturing assets would be sold or otherwise disposed of significantly before the end of their previously estimated useful lives. As a result, we compared the undiscounted future cash flows of our module manufacturing assets to the carrying value of the asset group and determined that the group was not recoverable. Accordingly, we measured the fair value of the asset group using a combination of income and cost valuation techniques and recorded impairment losses of $640.3 million for the year ended December 31, 2016 . During the year ended December 31, 2016 we also incurred charges of $14.1 million for severance benefits to terminated employees as we substantially reduced our workforce at our domestic and international facilities, including reductions in administrative and other staff, and $8.1 million for the closure of ancillary foreign operations, the write-off of operating supplies, and other miscellaneous charges. Substantially all amounts associated with these restructuring and asset impairment charges related to our modules segment and were classified as “ Restructuring and asset impairments ” on the consolidated statements of operations, and substantially all of the associated liabilities were paid or settled as of December 31, 2017 . Crystalline Silicon Module Manufacturing Restructuring In June 2016, our executive management elected to reallocate our crystalline silicon module production capacity to support next generation CdTe module offerings. As a result, we ended production of our crystalline silicon modules to focus on our core CdTe module technology and utility-scale PV solar power systems. The majority of our crystalline silicon module manufacturing associates were expected to be redeployed in other manufacturing operations. In connection with these restructuring activities, we incurred charges of $81.4 million during the year ended December 31, 2016 , which included (i) $35.9 million of impairment charges related to certain crystalline silicon module manufacturing equipment considered abandoned for accounting purposes, (ii) $35.8 million of impairment charges for developed technology intangible assets associated with our crystalline silicon module technology, (iii) $8.4 million of miscellaneous charges related to certain contract manufacturing agreements and the write-off of operating supplies, and (iv) $1.3 million of charges for severance benefits to terminated employees. All amounts associated with these charges related to our modules segment and were classified as “ Restructuring and asset impairments ” on the consolidated statements of operations. Other Restructuring During the year ended December 31, 2012, we recognized a liability for the expected repayment of certain customs tax benefits as part of a prior restructuring activity. In December 2017, we reversed this liability as a result of meeting certain investment certificate criteria associated with the commencement of operations at our previously announced manufacturing plant in Vietnam and recorded a $4.7 million benefit to “ Restructuring and asset impairments .”

Note 5. Business Acquisitions (

Note 5. Business Acquisitions (Notes)	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Business Acquisitions	5. Business Acquisitions Enki Technology In October 2016, we acquired 100% of the shares of Enki Technology, Inc. (“Enki”), a developer of advanced coating materials for the PV solar industry, for cash payments of $10.3 million , net of cash acquired of $0.3 million , and a promise to pay additional consideration of up to $7.0 million contingent on the achievement of certain production and module performance milestones. In connection with applying the acquisition method of accounting, $17.3 million of the purchase price consideration was assigned to an IPR&D intangible asset to be amortized over its useful life upon successful completion of the underlying projects, $4.4 million was assigned to a deferred tax liability, and $4.4 million was assigned to goodwill. The acquired IPR&D includes patents, technical information and know-how, and other proprietary information associated with the development and production of anti-reflective coating material that we expect to use in the production of our solar modules. Such technology is expected to improve our module conversion efficiency and overall durability at a lower cost structure compared to our current production processes.

Note 6. Goodwill and Intangible

Note 6. Goodwill and Intangible Assets (Notes)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	6. Goodwill and Intangible Assets Goodwill The changes in the carrying amount of goodwill, by reporting unit, for the years ended December 31, 2018 and 2017 were as follows (in thousands): Balance at December 31, 2017 Acquisitions (Impairments) Balance at December 31, 2018 Modules $ 407,827 $ — $ 407,827 Accumulated impairment losses (393,365 ) — (393,365 ) Total $ 14,462 $ — $ 14,462 Balance at December 31, 2016 Acquisitions (Impairments) Balance at December 31, 2017 Modules $ 407,827 $ — $ 407,827 Accumulated impairment losses (393,365 ) — (393,365 ) Total $ 14,462 $ — $ 14,462 2018 and 2017 Goodwill Impairment Testing We performed our annual impairment analysis in the fourth quarter of 2018 and 2017. ASC 350-20 provides that prior to performing a quantitative goodwill impairment test, companies are permitted to perform a qualitative assessment of whether it is more likely than not that a reporting unit’s fair value is less than its carrying value to determine whether it is necessary to perform a quantitative goodwill impairment test. Such qualitative assessment considers various factors, including macroeconomic conditions, industry and market considerations, cost factors, the overall financial performance of a reporting unit, and any other relevant events affecting our company or a reporting unit. We performed a qualitative assessment for our modules reporting unit in each respective period and concluded that it was not more likely than not that the fair value of the reporting unit was less than its carrying amount. Accordingly, a quantitative goodwill impairment test for this reporting unit was not required in either period. 2016 Goodwill Impairment Testing As part of our annual impairment analysis in the fourth quarter of 2016, we elected to perform a quantitative goodwill impairment test instead of first performing a qualitative goodwill impairment test. Such quantitative impairment test represented the comparison of the fair value of our reporting units with their carrying amounts, including goodwill. As of the date of our testing, our reporting units were consistent with our reportable segments: modules and systems. In determining the fair value of our reporting units, we used a combination of income and market based valuation techniques. Significant estimates used in our income based fair value calculations included: (i) future sales volumes and average selling prices per watt; (ii) cost per watt projections for module and system sales; (iii) future effective tax rates, which we estimated to be between 10% and 35% ; (iii) forecasts of capital expenditures and working capital requirements; (iv) discount rates, which we estimated to range between 11.5% and 18% ; and (v) future terminal values of our reporting units, which are based on their ability to exist into perpetuity. Significant estimates used in our market based fair value calculations included business enterprise values and revenue multiples of various publicly traded companies. The underlying assumptions used in the quantitative impairment test also considered our market capitalization as of the date of our testing and then-current solar industry market conditions. As a result of our testing, we determined that the estimated fair value of our modules reporting unit exceeded its carrying value indicating no impairment was necessary for this reporting unit. However, we determined that the estimated fair value of our systems reporting unit was less than its carrying value, which required us to determine the implied fair value of goodwill for the systems reporting unit by allocating the fair value of the systems reporting unit to its individual assets and liabilities, including any unrecognized intangible assets. Based on such calculation, the implied fair value of goodwill for the systems reporting unit was zero, and we recorded an impairment loss of $68.8 million . Such impairment was primarily driven by a strategic shift in the mix of our module and system net sales, which was approved by our board of directors in November 2016. This shift involved an expected reduction in the annual megawatts sold through systems business projects from approximately two gigawatts per year over the prior several years to approximately one gigawatt per year going forward. Other factors that contributed to the impairment included our reduced market capitalization and the challenging conditions within the solar industry as of the date of our testing. In June 2016, we impaired $6.1 million of goodwill associated with our crystalline silicon modules reporting unit as a result of the decision to end the related manufacturing operations and dispose of the reporting unit. See Note 4. “Restructuring and Asset Impairments” to our consolidated financial statements for further discussion related to this restructuring activity. Intangible Assets, Net The following tables summarize our intangible assets at December 31, 2018 and 2017 (in thousands): December 31, 2018 Gross Amount Accumulated Amortization Net Amount Developed technology $ 97,714 $ (33,093 ) $ 64,621 Power purchase agreements 6,486 (648 ) 5,838 Patents 7,408 (3,705 ) 3,703 Total $ 111,608 $ (37,446 ) $ 74,162 December 31, 2017 Gross Amount Accumulated Amortization Net Amount Developed technology $ 76,959 $ (24,140 ) $ 52,819 Power purchase agreements 6,486 (324 ) 6,162 Patents 7,068 (3,077 ) 3,991 In-process research and development (1) 17,255 — 17,255 Total $ 107,768 $ (27,541 ) $ 80,227 —————————— (1) During the year ended December 31, 2018 , $17.3 million of in-process research and development related to our prior Enki acquisition was reclassified to developed technology and began amortizing over its useful life of 10 years . Amortization expense for our intangible assets was $9.9 million , $8.3 million , and $10.1 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. Estimated future amortization expense for our definite-lived intangible assets was as follows at December 31, 2018 (in thousands): Amortization Expense 2019 $ 10,436 2020 10,786 2021 10,784 2022 10,759 2023 10,474 Thereafter 20,923 Total amortization expense $ 74,162

Note 7. Cash, Cash Equivalents,

Note 7. Cash, Cash Equivalents, and Marketable Securities (Notes)	12 Months Ended
	Dec. 31, 2018
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Cash, Cash Equivalents, and Marketable Securities	7. Cash, Cash Equivalents, and Marketable Securities Cash, cash equivalents, and marketable securities consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Cash and cash equivalents: Cash $ 1,202,774 $ 2,142,949 Money market funds 200,788 125,585 Total cash and cash equivalents 1,403,562 2,268,534 Marketable securities: Foreign debt 318,646 238,858 Foreign government obligations 98,621 152,850 U.S. debt 44,468 73,671 Time deposits 681,969 255,000 Total marketable securities 1,143,704 720,379 Total cash, cash equivalents, and marketable securities $ 2,547,266 $ 2,988,913 The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within our consolidated balance sheets as of December 31, 2018 and 2017 to the total of such amounts as presented in the consolidated statements of cash flows (in thousands): Balance Sheet Line Item 2018 2017 Cash and cash equivalents Cash and cash equivalents $ 1,403,562 $ 2,268,534 Restricted cash – current (1) Prepaid expenses and other current assets 19,671 11,120 Restricted cash – noncurrent (1) Restricted cash and investments 139,390 50,822 Total cash, cash equivalents, and restricted cash $ 1,562,623 $ 2,330,476 —————————— (1) See Note 8. “Restricted Cash and Investments” to our consolidated financial statements for discussion of our “Restricted cash” arrangements. During the years ended December 31, 2018 , 2017 , and 2016 , we sold marketable securities for proceeds of $10.8 million , $118.3 million , and $159.2 million , respectively, and realized gains of less than $0.1 million , less than $0.1 million , and $0.3 million , respectively, on such sales. See Note 11. “Fair Value Measurements” to our consolidated financial statements for information about the fair value of our marketable securities. The following tables summarize the unrealized gains and losses related to our available-for-sale marketable securities, by major security type, as of December 31, 2018 and 2017 (in thousands): As of December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign debt $ 320,056 $ 468 $ 1,878 $ 318,646 Foreign government obligations 99,189 — 568 98,621 U.S. debt 44,625 53 210 44,468 Time deposits 681,969 — — 681,969 Total $ 1,145,839 $ 521 $ 2,656 $ 1,143,704 As of December 31, 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign debt $ 240,643 $ 3 $ 1,788 $ 238,858 Foreign government obligations 153,999 — 1,149 152,850 U.S. debt 73,746 — 75 73,671 Time deposits 255,000 — — 255,000 Total $ 723,388 $ 3 $ 3,012 $ 720,379 As of December 31, 2018 , we identified 15 investments totaling $207.2 million that had been in a loss position for a period of time greater than 12 months with unrealized losses of $1.8 million . As of December 31, 2017 , we identified 16 investments totaling $210.3 million that had been in a loss position for a period of time greater than 12 months with unrealized losses of $1.9 million . The unrealized losses were primarily due to increases in interest rates relative to rates at the time of purchase. Based on the underlying credit quality of the investments, we do not intend to sell these securities prior to the recovery of our cost basis. Therefore, we did not consider these securities to be other-than-temporarily impaired. The following tables show unrealized losses and fair values for those marketable securities that were in an unrealized loss position as of December 31, 2018 and 2017 , aggregated by major security type and the length of time the marketable securities have been in a continuous loss position (in thousands): As of December 31, 2018 In Loss Position for Less Than 12 Months In Loss Position for 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Foreign debt $ 150,842 $ 802 $ 94,446 $ 1,076 $ 245,288 $ 1,878 Foreign government obligations — — 98,621 568 98,621 568 U.S. debt 15,356 32 14,085 178 29,441 210 Total $ 166,198 $ 834 $ 207,152 $ 1,822 $ 373,350 $ 2,656 As of December 31, 2017 In Loss Position for Less Than 12 Months In Loss Position for 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Foreign debt $ 119,869 $ 735 $ 88,919 $ 1,053 $ 208,788 $ 1,788 Foreign government obligations 31,467 289 121,383 860 152,850 1,149 U.S. debt $ 73,671 $ 75 $ — $ — $ 73,671 $ 75 Total $ 225,007 $ 1,099 $ 210,302 $ 1,913 $ 435,309 $ 3,012 The contractual maturities of our marketable securities as of December 31, 2018 were as follows (in thousands): Fair Value One year or less $ 904,384 One year to two years 161,961 Two years to three years 77,359 Total $ 1,143,704

Note 8. Restricted Cash and Inv

Note 8. Restricted Cash and Investments (Notes)	12 Months Ended
	Dec. 31, 2018
Restricted Cash and Investments [Abstract]
Restricted Cash and Investments	8. Restricted Cash and Investments Restricted cash and investments consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Restricted cash $ 139,390 $ 50,822 Restricted investments 179,000 373,961 Total restricted cash and investments (1) $ 318,390 $ 424,783 —————————— (1) There was an additional $19.7 million and $11.1 million of restricted cash included within “ Prepaid expenses and other current assets ” at December 31, 2018 and 2017 , respectively. At December 31, 2018 and 2017 , our restricted cash consisted of deposits held by various banks to secure certain of our letters of credit and other deposits designated for the construction or operation of systems projects as well as the payment of amounts related to project specific debt financings. Restricted cash also included certain deposits held in custodial accounts to fund the estimated future costs of our solar module collection and recycling obligations. See Note 15. “Commitments and Contingencies” to our consolidated financial statements for further discussion relating to our letters of credit. At December 31, 2018 and 2017 , our restricted investments consisted of long-term marketable securities that were also held in custodial accounts to fund the estimated future costs of collecting and recycling modules covered under our solar module collection and recycling program. As necessary, we fund any incremental amounts for our estimated collection and recycling obligations on an annual basis based on the estimated costs of collecting and recycling covered modules, estimated rates of return on our restricted investments, and an estimated solar module life of 25 years less amounts already funded in prior years. To ensure that amounts previously funded will be available in the future regardless of potential adverse changes in our financial condition (even in the case of our own insolvency), we have established a trust under which estimated funds are put into custodial accounts with an established and reputable bank, for which First Solar, Inc.; First Solar Malaysia Sdn. Bhd. (“FS Malaysia”); and First Solar Manufacturing GmbH are grantors. Trust funds may be disbursed for qualified module collection and recycling costs (including capital and facilities related recycling costs), payments to customers for assuming collection and recycling obligations, and reimbursements of any overfunded amounts. Investments in the trust must meet certain investment quality criteria comparable to highly rated government or agency bonds. During the year ended December 31, 2018 , we sold certain restricted investments for proceeds of $231.1 million and realized gains of $55.4 million on such sales as part of an effort to align the currencies of the investments with those of the corresponding collection and recycling liabilities and disburse $143.1 million of overfunded amounts. During the year ended December 31, 2016 , we sold certain restricted investments for proceeds of $118.2 million and realized gains of $41.3 million on such sales as part of a separate effort to align the currencies of the investments with those of the corresponding collection and recycling liabilities. See Note 11. “Fair Value Measurements” to our consolidated financial statements for information about the fair value of our restricted investments. The following tables summarize the unrealized gains and losses related to our restricted investments, by major security type, as of December 31, 2018 and 2017 (in thousands): As of December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign government obligations $ 73,798 $ 14,234 $ 235 $ 87,797 U.S. government obligations 97,223 416 6,436 91,203 Total $ 171,021 $ 14,650 $ 6,671 $ 179,000 As of December 31, 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign government obligations $ 127,436 $ 62,483 $ — $ 189,919 U.S. government obligations 174,624 12,944 3,526 184,042 Total $ 302,060 $ 75,427 $ 3,526 $ 373,961 As of December 31, 2018 , we identified six restricted investments totaling $87.4 million that had been in a loss position for a period of time greater than 12 months with unrealized losses of $6.4 million . As of December 31, 2017 , we identified six restricted investments totaling $107.7 million that had been in a loss position for a period of time greater than 12 months with unrealized losses of $3.5 million . The unrealized losses were primarily due to increases in interest rates relative to rates at the time of purchase. Based on the underlying credit quality of the investments, we do not intend to sell these securities prior to the recovery of our cost basis. Therefore, we did not consider these investments to be other-than-temporarily impaired. The following tables show unrealized losses and fair values for those restricted investments that were in an unrealized loss position as of December 31, 2018 and 2017 , aggregated by major security type and the length of time the restricted investments have been in a continuous loss position (in thousands): As of December 31, 2018 In Loss Position for In Loss Position for Total Fair Unrealized Fair Unrealized Fair Unrealized Foreign government obligations $ 41,335 $ 235 $ — $ — $ 41,335 $ 235 U.S. government obligations — — 87,401 6,436 87,401 6,436 Total $ 41,335 $ 235 $ 87,401 $ 6,436 $ 128,736 $ 6,671 As of December 31, 2017 In Loss Position for In Loss Position for Total Fair Unrealized Fair Unrealized Fair Unrealized U.S. government obligations $ — $ — $ 107,731 $ 3,526 $ 107,731 $ 3,526 Total $ — $ — $ 107,731 $ 3,526 $ 107,731 $ 3,526 As of December 31, 2018 , the contractual maturities of our restricted investments were between 11 years and 18 years .

Note 9. Consolidated Balance Sh

Note 9. Consolidated Balance Sheet Details (Notes)	12 Months Ended
	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Consolidated Balance Sheet Details	9. Consolidated Balance Sheet Details Accounts receivable trade, net Accounts receivable trade, net consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Accounts receivable trade, gross $ 129,644 $ 213,776 Allowance for doubtful accounts (1,362 ) (1,979 ) Accounts receivable trade, net $ 128,282 $ 211,797 At December 31, 2018 and 2017 , $8.5 million and $16.8 million , respectively, of our accounts receivable trade, net were secured by letters of credit, bank guarantees, or other forms of financial security issued by creditworthy financial institutions. Accounts receivable, unbilled and retainage Accounts receivable, unbilled and retainage consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Accounts receivable, unbilled $ 441,666 $ 172,594 Retainage 16,500 2,014 Accounts receivable, unbilled and retainage $ 458,166 $ 174,608 Inventories Inventories consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Raw materials $ 224,329 $ 148,968 Work in process 41,294 14,085 Finished goods 252,372 122,594 Inventories $ 517,995 $ 285,647 Inventories – current $ 387,912 $ 172,370 Inventories – noncurrent $ 130,083 $ 113,277 Prepaid expenses and other current assets Prepaid expenses and other current assets consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Prepaid expenses $ 90,981 $ 41,447 Prepaid income taxes 59,319 31,944 Indirect tax receivables 26,327 26,553 Restricted cash 19,671 11,120 Derivative instruments 2,364 4,303 Other current assets 44,399 42,535 Prepaid expenses and other current assets $ 243,061 $ 157,902 Property, plant and equipment, net Property, plant and equipment, net consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Land $ 14,382 $ 8,181 Buildings and improvements 567,605 424,266 Machinery and equipment 1,826,434 1,059,103 Office equipment and furniture 178,011 157,512 Leasehold improvements 49,055 48,951 Construction in progress 405,581 641,263 Property, plant and equipment, gross 3,041,068 2,339,276 Accumulated depreciation (1,284,857 ) (1,184,739 ) Property, plant and equipment, net $ 1,756,211 $ 1,154,537 Depreciation of property, plant and equipment was $109.1 million , $91.4 million , and $211.2 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. PV solar power systems, net PV solar power systems, net consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 PV solar power systems, gross $ 343,061 $ 451,045 Accumulated depreciation (34,421 ) (33,937 ) PV solar power systems, net $ 308,640 $ 417,108 Depreciation of PV solar power systems was $15.3 million , $19.8 million , and $11.7 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. Capitalized interest The cost of constructing project assets includes interest costs incurred during the construction period. The components of interest expense and capitalized interest were as follows during the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Interest cost incurred $ (31,752 ) $ (27,457 ) $ (26,157 ) Interest cost capitalized – property, plant and equipment — — 1,878 Interest cost capitalized – project assets 5,831 1,692 3,741 Interest expense, net $ (25,921 ) $ (25,765 ) $ (20,538 ) Project assets Project assets consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Project assets – development costs, including project acquisition and land costs $ 298,070 $ 250,590 Project assets – construction costs 200,359 252,127 Project assets 498,429 502,717 Project assets – current $ 37,930 $ 77,931 Project assets – noncurrent $ 460,499 $ 424,786 Other assets Other assets consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Deferred rent $ 27,249 $ 26,760 Indirect tax receivables 22,487 15,253 Notes receivable (1) 8,017 10,495 Income taxes receivable 4,444 4,454 Other 33,495 28,570 Other assets $ 95,692 $ 85,532 —————————— (1) In April 2009 , we entered into a credit facility agreement with a solar power project entity of one of our customers for an available amount of €17.5 million to provide financing for a PV solar power system. The credit facility bears interest at 8.0% per annum, payable quarterly, with the full amount due in December 2026. As of December 31, 2018 and 2017 , the balance outstanding on the credit facility was €7.0 million ( $8.0 million and $8.4 million , respectively). Accrued expenses Accrued expenses consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Accrued project costs $ 147,162 $ 55,834 Accrued property, plant and equipment 89,905 133,433 Accrued inventory 53,075 24,830 Accrued compensation and benefits 41,937 73,985 Product warranty liability (1) 27,657 28,767 Other 81,844 49,978 Accrued expenses $ 441,580 $ 366,827 —————————— (1) See Note 15. “Commitments and Contingencies” to our consolidated financial statements for discussion of our “Product warranty liability.” Other current liabilities Other current liabilities consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Derivative instruments $ 7,294 $ 27,297 Contingent consideration (1) 665 6,162 Financing liability (2) — 5,161 Indemnification liabilities (1) — 2,876 Other 6,421 7,261 Other current liabilities $ 14,380 $ 48,757 —————————— (1) See Note 15. “Commitments and Contingencies” to our consolidated financial statements for discussion of our “Contingent consideration” and “Indemnification liabilities” arrangements. (2) See Note 12. “Equity Method Investments” to our consolidated financial statements for discussion of the financing liabilities associated with our leaseback of the Maryland Solar project. Other liabilities Other liabilities consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Product warranty liability (1) $ 193,035 $ 195,507 Other taxes payable 83,058 89,724 Transition tax liability (2) 77,016 93,233 Deferred revenue 48,014 63,257 Derivative instruments 9,205 5,932 Contingent consideration (1) 2,250 3,153 Commercial letter of credit liability (1) — 43,396 Financing liability (3) — 29,822 Other 55,261 44,430 Other liabilities $ 467,839 $ 568,454 —————————— (1) See Note 15. “Commitments and Contingencies” to our consolidated financial statements for discussion of our “Product warranty liability,” “Contingent consideration,” and “Commercial letter of credit liability” arrangements. (2) See Note 19. “Income Taxes” to our consolidated financial statements for discussion of the one-time transition tax on accumulated earnings of foreign subsidiaries as a result of the Tax Act. (3) See Note 12. “Equity Method Investments” to our consolidated financial statements for discussion of the financing liabilities associated with our leaseback of the Maryland Solar project.

Note 10. Derivative Financial I

Note 10. Derivative Financial Instruments (Notes)	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	10. Derivative Financial Instruments As a global company, we are exposed in the normal course of business to interest rate and foreign currency risks that could affect our financial position, results of operations, and cash flows. We use derivative instruments to hedge against these risks and only hold such instruments for hedging purposes, not for speculative or trading purposes. Depending on the terms of the specific derivative instruments and market conditions, some of our derivative instruments may be assets and others liabilities at any particular balance sheet date. We report all of our derivative instruments at fair value and account for changes in the fair value of derivative instruments within “ Accumulated other comprehensive (loss) income ” if the derivative instruments qualify for hedge accounting. For those derivative instruments that do not qualify for hedge accounting (“economic hedges”), we record the changes in fair value directly to earnings. See Note 11. “Fair Value Measurements” to our consolidated financial statements for information about the techniques we use to measure the fair value of our derivative instruments. The following tables present the fair values of derivative instruments included in our consolidated balance sheets as of December 31, 2018 and 2017 (in thousands): December 31, 2018 Prepaid Expenses and Other Current Assets Other Current Liabilities Other Liabilities Derivatives designated as hedging instruments: Foreign exchange forward contracts $ 158 $ — $ — Total derivatives designated as hedging instruments $ 158 $ — $ — Derivatives not designated as hedging instruments: Foreign exchange forward contracts $ 2,206 $ 7,096 $ — Interest rate swap contracts — 198 9,205 Total derivatives not designated as hedging instruments $ 2,206 $ 7,294 $ 9,205 Total derivative instruments $ 2,364 $ 7,294 $ 9,205 December 31, 2017 Prepaid Expenses and Other Current Assets Other Current Liabilities Other Liabilities Derivatives designated as hedging instruments: Foreign exchange forward contracts $ 252 $ 13,240 $ — Total derivatives designated as hedging instruments $ 252 $ 13,240 $ — Derivatives not designated as hedging instruments: Foreign exchange forward contracts $ 4,051 $ 14,057 $ — Interest rate swap contracts — — 5,932 Total derivatives not designated as hedging instruments $ 4,051 $ 14,057 $ 5,932 Total derivative instruments $ 4,303 $ 27,297 $ 5,932 The following table presents the pretax amounts related to derivative instruments designated as cash flow hedges affecting accumulated other comprehensive income or loss and our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Foreign Exchange Forward Contracts Interest Rate Swap Contract Cross Currency Swap Contract Total Balance in accumulated other comprehensive (loss) income at December 31, 2015 $ 162 $ (16 ) $ (2,017 ) $ (1,871 ) Amounts recognized in other comprehensive (loss) income 2,513 (2 ) 5,108 7,619 Amounts reclassified to earnings impacting: Foreign currency loss, net — — (4,896 ) (4,896 ) Interest expense, net (119 ) 18 1,805 1,704 Balance in accumulated other comprehensive (loss) income at December 31, 2016 2,556 — — 2,556 Amounts recognized in other comprehensive (loss) income (4,468 ) — — (4,468 ) Amounts reclassified to earnings impacting: Other income, net 189 — — 189 Balance in accumulated other comprehensive (loss) income at December 31, 2017 (1,723 ) — — (1,723 ) Amounts recognized in other comprehensive (loss) income (3,760 ) — — (3,760 ) Amounts reclassified to earnings impacting: Net sales 1,698 — — 1,698 Cost of sales 212 — — 212 Foreign currency loss, net 5,448 — — 5,448 Other income, net (546 ) — — (546 ) Balance in accumulated other comprehensive (loss) income at December 31, 2018 $ 1,329 $ — $ — $ 1,329 We recorded no amounts related to ineffective portions of our derivative instruments designated as cash flow hedges during the years ended December 31, 2018 , 2017 , and 2016 . We recognized unrealized gains of $0.5 million and $0.7 million and unrealized losses of $0.9 million related to amounts excluded from effectiveness testing for our foreign exchange forward contracts designated as cash flow hedges within “ Other income, net ” during the years ended December 31, 2018 , 2017 , and 2016 , respectively. The following table presents gains and losses related to derivative instruments not designated as hedges affecting our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Amount of Gain (Loss) Recognized in Income Income Statement Line Item 2018 2017 2016 Foreign exchange forward contracts Foreign currency loss, net $ 12,113 $ (33,882 ) $ (14,002 ) Interest rate swap contracts Interest expense, net (8,643 ) (5,932 ) — Interest Rate Risk We use interest rate swap contracts to mitigate our exposure to interest rate fluctuations associated with certain of our debt instruments. We do not use such swap contracts for speculative or trading purposes. During the years ended December 31, 2018 and 2017 , all of our interest rate swap contracts related to project specific debt facilities. Such swap contracts did not qualify for accounting as cash flow hedges in accordance with ASC 815 due to our expectation to sell the associated projects before the maturity of their project specific debt financings and corresponding swap contracts. Accordingly, changes in the fair values of the swap contracts were recorded directly to “ Interest expense, net .” In December 2018, Royal Solar GK, our indirect wholly-owned subsidiary and project company, entered into an interest rate swap contract to hedge a portion of the floating rate term loan facility under the project’s Royal Solar Credit Facility (as defined in Note 14. “Debt” to our consolidated financial statements). Such swap had an initial notional value of ¥5.5 billion and entitled the project to receive a six-month floating Tokyo Interbank Offered Rate (“TIBOR”) plus 0.65% interest rate while requiring the project to pay a fixed rate of 1.34% . The notional amount of the interest rate swap contract is scheduled to proportionately adjust with the scheduled draws and principal payments on the underlying hedged debt. In December 2018, we completed the sale of our Royal Solar project, and its interest rate swap contract and outstanding loan balance were assumed by the customer. In August 2018, FS Japan Project 14 GK, our indirect wholly-owned subsidiary and project company, entered into an interest rate swap contract to hedge a portion of the floating rate senior loan facility under the project’s Mashiko Credit Agreement (as defined in Note 14. “Debt” to our consolidated financial statements). Such swap had an initial notional value of ¥5.5 billion and entitled the project to receive a six-month floating TIBOR interest rate while requiring the project to pay a fixed rate of 0.820% . The notional amount of the interest rate swap contract is scheduled to proportionately adjust with the scheduled draws and principal payments on the underlying hedged debt. In December 2018, we completed the sale of our Mashiko project, and its interest rate swap contract and outstanding loan balance were assumed by the customer. In May 2018, FS NSW Project No 1 Finco Pty Ltd, our indirectly wholly-owned subsidiary and project financing company, entered into various interest rate swap contracts to hedge the floating rate construction loan facility and a portion of the floating rate term loan facility under the associated project’s Beryl Credit Facility (as defined in Note 14. “Debt” to our consolidated financial statements). The swaps had an initial aggregate notional value of AUD 42.4 million and, depending on the loan facility being hedged, entitled the project to receive one-month or three-month floating Bank Bill Swap Bid (“BBSY”) interest rates while requiring the project to pay fixed rates of 2.0615% or 3.2020% . The notional amounts of the interest rate swap contracts are scheduled to proportionately adjust with the scheduled draws and principal payments on the underlying hedged debt. As of December 31, 2018 , the aggregate notional value of the interest rate swap contracts was AUD 103.4 million ( $72.9 million ). In March 2017, Manildra Finco Pty Ltd, our indirect wholly-owned subsidiary and project financing company, entered into various interest rate swap contracts to hedge a portion of the floating rate construction loan facility under the associated project’s Manildra Credit Facility (as defined in Note 14. “Debt” to our consolidated financial statements). Such swaps had an initial aggregate notional value of AUD 12.8 million and entitled the project to receive a one-month or three-month floating BBSY interest rate while requiring the project to pay a fixed rate of 3.13% . The notional amounts of the interest rate swap contracts are scheduled to proportionately adjust with the scheduled draws and principal payments on the underlying hedged debt. In September 2018, we completed the sale of our Manildra project, and its interest rate swap contracts and outstanding loan balance were assumed by the customer. As of December 31, 2017 , the aggregate notional value of the interest rate swap contracts was AUD 68.1 million ( $48.0 million ). In January 2017, FS Japan Project 12 GK, our indirect wholly-owned subsidiary and project company, entered into an interest rate swap contract to hedge a portion of the floating rate senior loan facility under the project’s Ishikawa Credit Agreement (as defined in Note 14. “Debt” to our consolidated financial statements). Such swap had an initial notional value of ¥5.7 billion and entitled the project to receive a six-month floating TIBOR plus 0.75% interest rate while requiring the project to pay a fixed rate of 1.482% . The notional amount of the interest rate swap contract is scheduled to proportionately adjust with the scheduled draws and principal payments on the underlying hedged debt. As of December 31, 2018 and 2017 , the notional value of the interest rate swap contract was ¥19.2 billion ( $174.1 million ) and ¥12.8 billion ( $115.7 million ), respectively. Foreign Currency Risk Cash Flow Exposure We expect certain of our subsidiaries to have future cash flows that will be denominated in currencies other than the subsidiaries’ functional currencies. Changes in the exchange rates between the functional currencies of our subsidiaries and the other currencies in which they transact will cause fluctuations in the cash flows we expect to receive or pay when these cash flows are realized or settled. Accordingly, we enter into foreign exchange forward contracts to hedge a portion of these forecasted cash flows. As of December 31, 2018 and 2017 , these foreign exchange forward contracts hedged our forecasted cash flows for periods up to six months and nine months , respectively. These foreign exchange forward contracts qualify for accounting as cash flow hedges in accordance with ASC 815, and we designated them as such. We initially report the effective portion of a derivative’s unrealized gain or loss in “ Accumulated other comprehensive (loss) income ” and subsequently reclassify amounts into earnings when the hedged transaction occurs and impacts earnings. We determined that these derivative financial instruments were highly effective as cash flow hedges as of December 31, 2018 and 2017 . As of December 31, 2018 and 2017 , the notional values associated with our foreign exchange forward contracts qualifying as cash flow hedges were as follows (notional amounts and U.S. dollar equivalents in millions): December 31, 2018 Currency Notional Amount USD Equivalent Australian dollar AUD 8.8 $6.2 December 31, 2017 Currency Notional Amount USD Equivalent Indian rupee INR 4,730.0 $74.1 Euro €15.7 $18.8 In the following 12 months, we expect to reclassify to earnings $1.3 million of net unrealized gains related to these forward contracts that are included in “ Accumulated other comprehensive (loss) income ” at December 31, 2018 as we realize the earnings effects of the related forecasted transactions. The amount we ultimately record to earnings will depend on the actual exchange rates when we realize the related forecasted transactions. Transaction Exposure and Economic Hedging Many of our subsidiaries have assets and liabilities (primarily cash, receivables, marketable securities, deferred taxes, payables, accrued expenses, and solar module collection and recycling liabilities) that are denominated in currencies other than the subsidiaries’ functional currencies. Changes in the exchange rates between the functional currencies of our subsidiaries and the other currencies in which these assets and liabilities are denominated will create fluctuations in our reported consolidated statements of operations and cash flows. We may enter into foreign exchange forward contracts or other financial instruments to economically hedge assets and liabilities against the effects of currency exchange rate fluctuations. The gains and losses on such foreign exchange forward contracts will economically offset all or part of the transaction gains and losses that we recognize in earnings on the related foreign currency denominated assets and liabilities. We also enter into foreign exchange forward contracts to economically hedge balance sheet and other exposures related to transactions between certain of our subsidiaries and transactions with third parties. Such contracts are considered economic hedges and do not qualify for hedge accounting. Accordingly, we recognize gains or losses from the fluctuations in foreign exchange rates and the fair value of these derivative contracts in “ Foreign currency loss, net ” on our consolidated statements of operations. These contracts mature at various dates within the next three months . As of December 31, 2018 and 2017 , the notional values of our foreign exchange forward contracts that do not qualify for hedge accounting were as follows (notional amounts and U.S. dollar equivalents in millions): December 31, 2018 Transaction Currency Notional Amount USD Equivalent Purchase Australian dollar AUD 2.1 $1.5 Sell Australian dollar AUD 52.9 $37.3 Purchase Brazilian real BRL 8.5 $2.2 Sell Canadian dollar CAD 2.9 $2.1 Sell Chilean peso CLP 3,506.6 $5.1 Purchase Euro €115.2 $131.9 Sell Euro €191.8 $219.7 Sell Indian rupee INR 789.2 $11.3 Purchase Japanese yen ¥931.6 $8.4 Sell Japanese yen ¥23,858.8 $216.2 Purchase Malaysian ringgit MYR 34.3 $8.3 Sell Malaysian ringgit MYR 53.8 $12.9 Sell Mexican peso MXN 37.3 $1.9 Purchase Singapore dollar SGD 3.8 $2.8 December 31, 2017 Transaction Currency Notional Amount USD Equivalent Purchase Australian dollar AUD 12.7 $9.9 Sell Australian dollar AUD 56.8 $44.4 Sell Canadian dollar CAD 1.7 $1.4 Sell Chilean peso CLP 10,180.9 $16.6 Purchase Chinese yuan CNY 13.8 $2.1 Purchase Euro €151.4 $181.6 Sell Euro €193.2 $231.7 Purchase Indian rupee INR 645.7 $10.1 Sell Indian rupee INR 8,376.0 $131.1 Sell Japanese yen ¥23,922.2 $212.6 Purchase Malaysian ringgit MYR 31.0 $7.7 Sell Malaysian ringgit MYR 336.5 $83.1 Sell Singapore dollar SGD 3.1 $2.3 Purchase South African rand ZAR 12.5 $1.0 Sell South African rand ZAR 61.1 $5.0

Note 11. Fair Value Measurement

Note 11. Fair Value Measurements (Notes)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	11. Fair Value Measurements The following is a description of the valuation techniques that we use to measure the fair value of assets and liabilities that we measure and report at fair value on a recurring basis: • Cash Equivalents. At December 31, 2018 and 2017 , our cash equivalents consisted of money market funds. We value our cash equivalents using observable inputs that reflect quoted prices for securities with identical characteristics, and accordingly, we classify the valuation techniques that use these inputs as Level 1. • Marketable Securities and Restricted Investments. At December 31, 2018 and 2017 , our marketable securities consisted of foreign debt, foreign government obligations, U.S. debt, and time deposits, and our restricted investments consisted of foreign and U.S. government obligations. We value our marketable securities and restricted investments using observable inputs that reflect quoted prices for securities with identical characteristics or quoted prices for securities with similar characteristics and other observable inputs (such as interest rates that are observable at commonly quoted intervals). Accordingly, we classify the valuation techniques that use these inputs as either Level 1 or Level 2 depending on the inputs used. We also consider the effect of our counterparties’ credit standing in these fair value measurements. • Derivative Assets and Liabilities . At December 31, 2018 and 2017 , our derivative assets and liabilities consisted of foreign exchange forward contracts involving major currencies and interest rate swap contracts involving major interest rates. Since our derivative assets and liabilities are not traded on an exchange, we value them using standard industry valuation models. As applicable, these models project future cash flows and discount the amounts to a present value using market-based observable inputs, including interest rate curves, credit risk, foreign exchange rates, and forward and spot prices for currencies. These inputs are observable in active markets over the contract term of the derivative instruments we hold, and accordingly, we classify the valuation techniques as Level 2. In evaluating credit risk, we consider the effect of our counterparties’ and our own credit standing in the fair value measurements of our derivative assets and liabilities, respectively. At December 31, 2018 and 2017 , the fair value measurements of our assets and liabilities measured on a recurring basis were as follows (in thousands): Fair Value Measurements at Reporting Date Using December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Cash equivalents: Money market funds $ 200,788 $ 200,788 $ — $ — Marketable securities: Foreign debt 318,646 — 318,646 — Foreign government obligations 98,621 — 98,621 — U.S. debt 44,468 — 44,468 — Time deposits 681,969 681,969 — — Restricted investments 179,000 — 179,000 — Derivative assets 2,364 — 2,364 — Total assets $ 1,525,856 $ 882,757 $ 643,099 $ — Liabilities: Derivative liabilities $ 16,499 $ — $ 16,499 $ — Fair Value Measurements at Reporting Date Using December 31, 2017 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Cash equivalents: Money market funds $ 125,585 $ 125,585 $ — $ — Marketable securities: Foreign debt 238,858 — 238,858 — Foreign government obligations 152,850 — 152,850 — U.S. debt 73,671 — 73,671 — Time deposits 255,000 255,000 — — Restricted investments 373,961 — 373,961 — Derivative assets 4,303 — 4,303 — Total assets $ 1,224,228 $ 380,585 $ 843,643 $ — Liabilities: Derivative liabilities $ 33,229 $ — $ 33,229 $ — Fair Value of Financial Instruments At December 31, 2018 and 2017 , the carrying values and fair values of our financial instruments not measured at fair value were as follows (in thousands): December 31, 2018 December 31, 2017 Carrying Value Fair Value Carrying Value Fair Value Assets: Notes receivable – noncurrent $ 8,017 $ 8,010 $ 10,495 $ 10,516 Notes receivable, affiliate – current — — 20,411 23,317 Notes receivable, affiliates – noncurrent 22,832 24,295 48,370 47,441 Liabilities: Long-term debt, including current maturities (1) $ 479,157 $ 470,124 $ 406,388 $ 416,486 —————————— (1) Excludes capital lease obligations and unamortized discounts and issuance costs. The carrying values in our consolidated balance sheets of our trade accounts receivable, unbilled accounts receivable and retainage, restricted cash, accounts payable, and accrued expenses approximated their fair values due to their nature and relatively short maturities; therefore, we excluded them from the foregoing table. The fair value measurements for our notes receivable and long-term debt are considered Level 2 measurements under the fair value hierarchy. Credit Risk We have certain financial and derivative instruments that subject us to credit risk. These consist primarily of cash, cash equivalents, marketable securities, accounts receivable, restricted cash and investments, notes receivable, and foreign exchange forward contracts. We are exposed to credit losses in the event of nonperformance by the counterparties to our financial and derivative instruments. We place cash, cash equivalents, marketable securities, restricted cash and investments, and foreign exchange forward contracts with various high-quality financial institutions and limit the amount of credit risk from any one counterparty. We continuously evaluate the credit standing of our counterparty financial institutions. Our net sales are primarily concentrated among a limited number of customers. We monitor the financial condition of our customers and perform credit evaluations whenever considered necessary. Depending upon the sales arrangement, we may require some form of payment security from our customers, including advance payments, parent guarantees, bank guarantees, surety bonds, or commercial letters of credit. We also have PPAs that subject us to credit risk in the event our offtake counterparties are unable to fulfill their contractual obligations, which may adversely affect our project assets and certain receivables. Accordingly, we closely monitor the credit standing of existing and potential offtake counterparties to limit such risks.

Note 12. Equity Method Investme

Note 12. Equity Method Investments (Notes)	12 Months Ended
	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	12. Equity Method Investments From time to time, we may enter into investments or other strategic arrangements to expedite our penetration of certain markets and establish relationships with potential customers. We may also enter into strategic arrangements with customers or other entities to maximize the value of particular projects. Some of these arrangements may involve significant investments or other allocations of capital. Investments in unconsolidated entities for which we have significant influence, but not control, over the entities’ operating and financial activities are accounted for under the equity method of accounting. The following table summarizes our equity method investments as of December 31, 2018 and 2017 (in thousands): 2018 2017 8point3 Operating Company, LLC $ — $ 199,477 Clean Energy Collective, LLC — 6,521 Other 3,186 11,232 Equity method investments $ 3,186 $ 217,230 8point3 Operating Company, LLC In June 2015, 8point3, a limited partnership formed with SunPower Corporation (together with First Solar, the “Sponsors”), completed its initial public offering (the “IPO”) pursuant to a Registration Statement on Form S-1, as amended. As part of the IPO, the Sponsors contributed interests in various projects to OpCo in exchange for voting and economic interests in the entity, and 8point3 acquired an economic interest in OpCo using proceeds from the IPO. After the formation of 8point3, the Sponsors, from time to time, sold interests in solar projects to 8point3, which owns and operates such portfolio of solar energy generation projects. In February 2018, we entered into an agreement with CD Clean Energy and Infrastructure V JV, LLC, an equity fund managed by Capital Dynamics and certain other co-investors and other parties, pursuant to which the purchasers agreed to acquire our interests in 8point3 and its subsidiaries. In June 2018, we completed the sale of those interests and received net proceeds of $240.0 million after the payment of fees, expenses, and other amounts. We accounted for our interest in OpCo, a subsidiary of 8point3, under the equity method of accounting as we were able to exercise significant influence over 8point3 due to our representation on the board of directors of its general partner and certain of our associates serving as officers of its general partner. We recognized equity in earnings, net of tax, from our investment in OpCo of $39.7 million , $9.8 million , and $32.6 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. Our equity in earnings for the year ended December 31, 2018 included a gain of $40.3 million , net of tax, for the sale of our interests in 8point3 and its subsidiaries. Our equity in earnings for the year ended December 31, 2016 included a gain of $8.5 million , net of tax, following OpCo’s issuance of 8,050,000 shares to 8point3 as part of its public offering of a corresponding number of shares. During the years ended December 31, 2018 , 2017 , and 2016 , we received distributions from OpCo of $12.4 million , $23.0 million , and $5.3 million , respectively. In connection with the IPO, we also entered into an agreement with a subsidiary of 8point3 to lease back one of our originally contributed projects, Maryland Solar, until December 31, 2019. Under the terms of the agreement, we make fixed rent payments to 8point3’s subsidiary and are entitled to all of the energy generated by the project. Due to certain continuing involvement with the project, we accounted for the leaseback agreement as a financing transaction until the sale of our interests in 8point3 and its subsidiaries in June 2018. Following the sale of such interests, the Maryland Solar project qualified for sale-leaseback accounting, and we recognized net revenue of $32.0 million from the sale of the project. As of December 31, 2017 , the financing obligation associated with the leaseback was $35.0 million . In March 2018, FirstEnergy Solutions Corp. (“FirstEnergy”), the off-taker for the Maryland Solar PPA, filed for chapter 11 bankruptcy protection, and in April 2018, FirstEnergy filed a motion for entry of an order authorizing FirstEnergy and its affiliates to reject certain energy contracts, including the Maryland Solar PPA. In August 2018, the bankruptcy court granted the motion. As a result, we began selling energy generated by the Maryland Solar project on an open contract basis in October 2018. In December 2016, we completed the sale of our remaining 34% interest in the 300 MW AC Desert Stateline project located in San Bernardino County, California to OpCo and received a $50.0 million promissory note as part of the consideration for the sale. In June 2018, the outstanding balance on the promissory note of $47.8 million was repaid in conjunction with the sale of our interests in 8point3 and its subsidiaries. As of December 31, 2017 , the balance outstanding on the promissory note was $48.4 million . We provide O&M services to certain of 8point3’s partially owned project entities, including SG2 Holdings, LLC; Lost Hills Blackwell Holdings, LLC; NS Solar Holdings, LLC; Kingbird Solar A, LLC; Kingbird Solar B, LLC; and Desert Stateline LLC. Prior to the sale of our interests in 8point3 and its subsidiaries, we recognized revenue of $5.6 million , $11.0 million , and $6.1 million for such O&M services during the years ended December 31, 2018 , 2017 , and 2016 , respectively. Clean Energy Collective, LLC In November 2014, we entered into various agreements to purchase a minority ownership interest in Clean Energy Collective, LLC (“CEC”). This investment provided us with additional access to the distributed generation market and a partner to develop and market community solar offerings to North American residential customers and businesses directly on behalf of client utility companies. As part of the investment, we also received a warrant to purchase additional ownership interests in CEC. In addition to our equity investment, we also entered into a term loan agreement and a convertible loan agreement with CEC in November 2014 and February 2016, respectively. Our term loan bears interest at 16% per annum, and our convertible loan bears interest at 10% per annum. In November 2018, we amended the terms of the loan agreements to (i) extend their maturity to June 2020, (ii) waive the conversion features on our convertible loan, and (iii) increase the frequency of interest payments, subject to certain conditions. As of December 31, 2018 and 2017 , the aggregate balance outstanding on the loans was $22.8 million and $20.4 million , respectively. In September 2018, the board of managers of CEC evaluated restructuring proposals to address certain liquidity issues that were adversely affecting its operations. Such restructuring provided for the subsequent repayment of CEC’s outstanding debt, including our loan agreements, but indicated that a decrease in the value of our investment in CEC may have occurred that was other than temporary. Accordingly, in September 2018, we recorded an impairment loss of $3.5 million , net of tax, for our remaining investment in CEC based on the proposed restructuring. In September 2018, we also recorded an impairment loss of $1.8 million in “Other (loss) income, net” for the expected surrender of our warrant. In November 2018, the owners and lenders of CEC entered into various restructuring agreements based on the previously proposed arrangement. In January 2019, the restructuring was finalized, which resulted in a dilution of our ownership interest in CEC, the loss of representation on the company’s board of managers, and the surrender of our warrant. As of December 31, 2018 , CEC was considered a variable interest entity, or VIE, and our 25% ownership interest in and loans to the company were considered variable interests. We accounted for our investment in CEC under the equity method of accounting as we were not the primary beneficiary of the company given that we did not have the power to make decisions over the activities that most significantly impact the company’s economic performance. Under the equity method of accounting, we recognized equity in earnings for our proportionate share of CEC’s net income or loss including adjustments for the amortization of a basis difference resulting from the cost of our investment differing from our proportionate share of CEC’s equity. During the years ended December 31, 2018 , 2017 , and 2016 , we recognized losses, net of tax, of $4.3 million , $2.6 million , and $3.6 million , respectively, from our investment in CEC, including the impairment of our remaining investment described above. During the year ended December 31, 2017 , we sold 21 MW DC of solar modules to CEC and recognized revenue of $7.6 million . Summarized Financial Information The following table presents summarized financial information, in the aggregate, for our significant equity method investees, as provided to us by the investees (in thousands): Fiscal 2018 Fiscal 2017 Fiscal 2016 Summary statement of operations information: Net sales $ 28,736 $ 70,089 $ 125,643 Operating (loss) income (38,606 ) 24,661 55,266 Net (loss) income (1) (39,280 ) 46,713 63,893 Net (loss) income attributable to equity method investees (1) (2) (45,228 ) 53,183 190,240 As of Fiscal 2018 As of Fiscal 2017 Summary balance sheet information: Current assets $ — $ 36,744 Long-term assets — 1,573,115 Current liabilities — 7,648 Long-term liabilities — 706,885 Noncontrolling interests, including redeemable noncontrolling interests — 72,945 —————————— (1) The difference between Net (loss) income and Net (loss) income attributable to equity method investees is due to OpCo’s tax equity financing facilities with third-party investors that hold noncontrolling ownership interests in certain of its subsidiaries. Accordingly, earnings or losses are allocated to such tax equity investors using the Hypothetical Liquidation at Book Value (or “HLBV”) method. During the fiscal 2018, 2017, and 2016 periods, OpCo allocated certain losses to such third-party investors under the HLBV method, which represented the difference between Net (loss) income and Net (loss) income attributable to equity method investees. (2) Our proportionate share of OpCo’s net loss for fiscal 2018 excluded the investee’s impairment loss related to the Maryland Solar project as we accounted for the sale-leaseback of the project as a financing transaction and the associated financing liability exceeded the carrying value of the project.

Note 13. Solar Module Collectio

Note 13. Solar Module Collection and Recycling Liability (Notes)	12 Months Ended
	Dec. 31, 2018
Solar Module Collection and Recycling Liability [Abstract]
Solar Module Collection and Recycling Liability	13. Solar Module Collection and Recycling Liability We previously established a module collection and recycling program to collect and recycle modules sold and covered under such program once the modules reach the end of their useful lives. For legacy customer sales contracts that were covered under this program, we agreed to pay the costs for the collection and recycling of qualifying solar modules, and the end-users agreed to notify us, disassemble their solar power systems, package the solar modules for shipment, and revert ownership rights over the modules back to us at the end of the modules’ service lives. Accordingly, we recorded any collection and recycling obligations within “Cost of sales” at the time of sale based on the estimated cost to collect and recycle the covered solar modules. During the years ended December 31, 2018 , 2017 , and 2016 , substantially all of our modules sold were not covered by our collection and recycling program as we discontinued including such program in our sales contracts. We estimate the cost of our collection and recycling obligations based on the present value of the expected probability-weighted future cost of collecting and recycling the solar modules, which includes estimates for the cost of packaging materials; the cost of freight from the solar module installation sites to a recycling center; material, labor, and capital costs; the scale of recycling centers; and an estimated third-party profit margin and return on risk for collection and recycling services. We base these estimates on (i) our experience collecting and recycling our solar modules, (ii) the expected timing of when our solar modules will be returned for recycling, and (iii) the expected economic factors at the time the solar modules will be collected and recycled. In the periods between the time of sale and the related settlement of the collection and recycling obligation, we accrete the carrying amount of the associated liability by applying the discount rate used for its initial measurement. We classify accretion as an operating expense within “ Selling, general and administrative ” expense on our consolidated statements of operations. We periodically review our estimates of expected future recycling costs and may adjust our liability accordingly. During the year ended December 31, 2018 , we reduced our module collection and recycling liability by $34.2 million primarily due to higher by-product credits for glass, lower capital costs resulting from the expanded scale of our recycling facilities, and adjustments to certain valuation assumptions driven by our increased experience with module recycling. During the year ended December 31, 2017 , we reduced our module collection and recycling liability by $15.8 million primarily as a result of updates to several valuation assumptions, including a decrease in certain inflation rates. Our module collection and recycling liability was $134.4 million and $166.6 million as of December 31, 2018 and 2017 , respectively. During the years ended December 31, 2018 and 2017 , we recognized net benefits of $25.0 million and $13.2 million , respectively, to cost of sales as a result of the reductions in our module collection and recycling liability described above. During the year ended December 31, 2018 , we also recognized a net benefit of $2.9 million to accretion expense primarily due to the reduction in the liability. During the years ended December 31, 2017 and 2016 , we recognized net accretion expense of $3.9 million and $6.1 million , respectively, associated with the liability. As of December 31, 2018 , a 1% increase in the annualized inflation rate used in our estimated future collection and recycling cost per module would increase our liability by $25.7 million , and a 1% decrease in that rate would decrease our liability by $21.7 million . See Note 8. “Restricted Cash and Investments” to our consolidated financial statements for more information about our arrangements for funding this liability.

Note 14. Debt (Notes)

Note 14. Debt (Notes)	12 Months Ended
	Dec. 31, 2018
Debt Instruments [Abstract]
Debt	14. Debt Our long-term debt consisted of the following at December 31, 2018 and 2017 (in thousands): Balance (USD) Loan Agreement Currency 2018 2017 Revolving Credit Facility USD $ — $ — Luz del Norte Credit Facilities USD 188,849 185,675 Ishikawa Credit Agreement JPY 157,834 121,446 Japan Credit Facility JPY — 10,710 Tochigi Credit Facility JPY 25,468 — Mashiko Credit Agreement JPY — — Royal Solar Credit Facility JPY — — Marikal Credit Facility INR — 7,384 Hindupur Credit Facility INR — 18,722 Anantapur Credit Facility INR 16,101 — Tungabhadra Credit Facility INR 13,934 — Manildra Credit Facility AUD — 62,451 Beryl Credit Facility AUD 76,971 — Capital lease obligations Various — 156 Long-term debt principal 479,157 406,544 Less: unamortized discounts and issuance costs (12,366 ) (13,004 ) Total long-term debt 466,791 393,540 Less: current portion (5,570 ) (13,075 ) Noncurrent portion $ 461,221 $ 380,465 Revolving Credit Facility Our amended and restated credit agreement with several financial institutions as lenders and JPMorgan Chase Bank, N.A. as administrative agent provides us with a senior secured credit facility (the “Revolving Credit Facility”) with an aggregate borrowing capacity of $500.0 million , which we may increase to $750.0 million , subject to certain conditions. Borrowings under the credit facility bear interest at (i) London Interbank Offered Rate (“LIBOR”), adjusted for Eurocurrency reserve requirements, plus a margin of 2.00% or (ii) a base rate as defined in the credit agreement plus a margin of 1.00% depending on the type of borrowing requested . These margins are also subject to adjustment depending on our consolidated leverage ratio. We had no borrowings under our Revolving Credit Facility as of December 31, 2018 and 2017 and had issued $66.0 million and $57.5 million , respectively, of letters of credit using availability under the facility. Loans and letters of credit issued under the Revolving Credit Facility are jointly and severally guaranteed by First Solar, Inc.; First Solar Electric, LLC; First Solar Electric (California), Inc.; and First Solar Development, LLC and are secured by interests in substantially all of the guarantors’ tangible and intangible assets other than certain excluded assets. In addition to paying interest on outstanding principal under the Revolving Credit Facility, we are required to pay a commitment fee at a rate of 0.30% per annum, based on the average daily unused commitments under the facility, which may also be adjusted due to changes in our consolidated leverage ratio. We also pay a letter of credit fee based on the applicable margin for Eurocurrency revolving loans on the face amount of each letter of credit and a fronting fee of 0.125% . Our Revolving Credit Facility matures in July 2022. Luz del Norte Credit Facilities In August 2014, Parque Solar Fotovoltaico Luz del Norte SpA (“Luz del Norte”), our indirect wholly-owned subsidiary and project company, entered into credit facilities with the Overseas Private Investment Corporation (“OPIC”) and the International Finance Corporation (“IFC”) to provide limited-recourse senior secured debt financing for the design, development, financing, construction, testing, commissioning, operation, and maintenance of a 141 MW AC PV solar power plant located near Copiapó, Chile. At the same time, Luz del Norte also entered into a Chilean peso facility (the “VAT facility” and together with the OPIC and IFC loans, the “Luz del Norte Credit Facilities”) with Banco de Crédito e Inversiones to fund Chilean value added tax associated with the construction of the Luz del Norte project. In March 2017, we repaid the remaining balance on the VAT facility. In March 2017, we amended the terms of the OPIC and IFC credit facilities. Such amendments (i) allowed for the capitalization of accrued and unpaid interest through March 15, 2017, along with the capitalization of certain future interest payments as variable rate loans under the credit facilities, (ii) allowed for the conversion of certain fixed rate loans to variable rate loans upon scheduled repayment, (iii) extended the maturity of the OPIC and IFC loans until June 2037, and (iv) canceled the remaining borrowing capacity under the OPIC and IFC credit facilities with the exception of the capitalization of certain future interest payments. As of December 31, 2018 and 2017 , the balance outstanding on the OPIC loans was $141.4 million and $139.0 million , respectively. As of December 31, 2018 and 2017 , the balance outstanding on the IFC loans was $47.4 million and $46.6 million , respectively. The OPIC and IFC loans are secured by liens over all of Luz del Norte’s assets and by a pledge of all of the equity interests in the entity. In February 2019, we received a waiver for a technical noncompliance related to the Luz Del Norte Credit Facilities as of December 31, 2018 . We expect to cure such technical noncompliance within the waiver period, which expires in June 2019. Ishikawa Credit Agreement In December 2016, FS Japan Project 12 GK (“Ishikawa”), our indirect wholly-owned subsidiary and project company, entered into a credit agreement (the “Ishikawa Credit Agreement”) with Mizuho Bank, Ltd. for aggregate borrowings up to ¥27.3 billion ( $247.4 million ) for the development and construction of a 59 MW AC PV solar power plant located in Ishikawa, Japan. The credit agreement consists of a ¥24.0 billion ( $217.5 million ) senior loan facility, a ¥2.1 billion ( $19.0 million ) consumption tax facility, and a ¥1.2 billion ( $10.9 million ) letter of credit facility. The senior loan facility matures in October 2036, and the consumption tax facility matures in April 2020. The credit agreement is secured by pledges of Ishikawa’s assets, accounts, material project documents, and by the equity interests in the entity. As of December 31, 2018 and 2017 , the balance outstanding on the credit agreement was $157.8 million and $121.4 million , respectively. Japan Credit Facility In September 2015, First Solar Japan GK, our wholly-owned subsidiary, entered into a construction loan facility with Mizuho Bank, Ltd. for borrowings up to ¥4.0 billion ( $36.3 million ) for the development and construction of utility-scale PV solar power plants in Japan (the “Japan Credit Facility”). In September 2018, First Solar Japan GK renewed the facility for an additional one-year period until September 2019. The facility is guaranteed by First Solar, Inc. and secured by pledges of certain projects’ cash accounts and other rights in the projects. As of December 31, 2018 and 2017 , the balance outstanding on the facility was zero and $10.7 million , respectively. Tochigi Credit Facility In June 2017, First Solar Japan GK, our wholly-owned subsidiary, entered into a term loan facility with Mizuho Bank, Ltd. for borrowings up to ¥7.0 billion ( $63.4 million ) for the development of utility-scale PV solar power plants in Japan (the “Tochigi Credit Facility”). The term loan facility matures in March 2021. The facility is guaranteed by First Solar, Inc. and secured by pledges of certain of First Solar Japan GK’s accounts. As of December 31, 2018 and 2017 , the balance outstanding on the term loan facility was $25.5 million and zero , respectively. Mashiko Credit Agreement In March 2018, FS Japan Project 14 GK (“Mashiko”), our indirect wholly-owned subsidiary and project company, entered into a credit agreement (the “Mashiko Credit Agreement”) with Mizuho Bank, Ltd. for aggregate borrowings up to ¥9.2 billion ( $83.4 million ) for the development and construction of a 19 MW AC PV solar power plant located in Tochigi, Japan. The credit agreement consisted of a ¥8.1 billion ( $73.4 million ) senior loan facility, a ¥0.7 billion ( $6.3 million ) consumption tax facility, and a ¥0.4 billion ( $3.6 million ) letter of credit facility. In December 2018, we completed the sale of our Mashiko project, and the outstanding balance of the Mashiko Credit Agreement of $57.2 million was assumed by the customer. Royal Solar Credit Facility In November 2018, Royal Solar GK, our indirect wholly-owned subsidiary and project company, entered into a credit agreement (the “Royal Solar Credit Facility”) with Shinsei Bank, Ltd. for aggregate borrowings up to ¥11.8 billion ( $106.9 million ) for the development and construction of a 25 MW AC PV solar power plant located in Gunma, Japan. The credit facility consisted of a ¥10.5 billion ( $95.2 million ) term loan facility, a ¥0.9 billion ( $8.2 million ) consumption tax facility, and a ¥0.4 billion ( $3.6 million ) debt service reserve facility. In December 2018, we completed the sale of our Royal Solar project, and the outstanding balance of the Royal Solar Credit Facility of $67.2 million was assumed by the customer. Marikal Credit Facility In March 2015, FS India Devco Private Limited (previously known as Marikal Solar Parks Private Limited), our indirect wholly-owned subsidiary and project company, entered into a term loan facility (the “Marikal Credit Facility”) with Axis Bank as administrative agent for aggregate borrowings up to INR 0.5 billion ( $7.8 million ) for the development and construction of a 10 MW AC PV solar power plant located in Telangana, India. In May 2018, we repaid the remaining $6.8 million principal balance on the term loan facility. As of December 31, 2017 , the balance outstanding on the term loan facility was $7.4 million . Hindupur Credit Facility In November 2016, Hindupur Solar Parks Private Limited, our indirect wholly-owned subsidiary and project company, entered into a term loan facility (the “Hindupur Credit Facility”) with Yes Bank Limited for borrowings up to INR 4.3 billion ( $61.4 million ) for costs related to an 80 MW AC portfolio of PV solar power plants located in Andhra Pradesh, India. The term loan facility had a letter of credit sub-limit of INR 3.2 billion ( $45.7 million ), which was used for project related costs. In March 2018, we completed the sale of our Hindupur projects, and the outstanding balance of the Hindupur Credit Facility of $17.0 million was assumed by the customer. As of December 31, 2017 , we had issued INR 2.9 billion ( $41.4 million ) of letters of credit under the term loan facility, and the balance outstanding on the term loan facility was $18.7 million . Anantapur Credit Facility In March 2018, Anantapur Solar Parks Private Limited, our indirect wholly-owned subsidiary and project company, entered into a term loan facility (the “Anantapur Credit Facility”) with J.P. Morgan Securities India Private Limited for borrowings up to INR 1.2 billion ( $17.1 million ) for costs related to a 20 MW AC PV solar power plant located in Karnataka, India. The term loan facility matures in February 2021 and is secured by a letter of credit issued by JPMorgan Chase Bank, N.A., Singapore, in favor of the lender. Such letter of credit is secured by a cash deposit placed by First Solar FE Holdings Pte. Ltd. As of December 31, 2018 , the balance outstanding on the term loan facility was $16.1 million . Tungabhadra Credit Facility In March 2018, Tungabhadra Solar Parks Private Limited, our indirect wholly-owned subsidiary and project company, entered into a term loan facility (the “Tungabhadra Credit Facility”) with J.P. Morgan Securities India Private Limited for borrowings up to INR 1.0 billion ( $14.3 million ) for costs related to a 20 MW AC PV solar power plant located in Karnataka, India. The term loan facility matures in February 2021 and is secured by a letter of credit issued by JPMorgan Chase Bank, N.A., Singapore, in favor of the lender. Such letter of credit is secured by a cash deposit placed by First Solar FE Holdings Pte. Ltd. As of December 31, 2018 , the balance outstanding on the term loan facility was $13.9 million . Manildra Credit Facility In March 2017, Manildra Finco Pty Ltd, our indirect wholly-owned subsidiary and project financing company, entered into a term loan facility (the “Manildra Credit Facility”) with Société Générale S.A. and The Bank of Tokyo-Mitsubishi UFJ, Ltd. for aggregate borrowings up to AUD 81.7 million ( $57.6 million ) for costs related to a 49 MW AC PV solar power plant located in New South Wales, Australia. The credit facility consisted of an AUD 75.7 million ( $53.4 million ) construction loan facility and an additional AUD 6.0 million ( $4.2 million ) goods and service tax facility (“GST facility”) to fund certain taxes associated with the construction of the associated project. In September 2018, we completed the sale of our Manildra project, and the outstanding balance of the Manildra Credit Facility of $56.1 million was assumed by the customer. As of December 31, 2017 , the balance outstanding on the credit facility was $62.5 million . Beryl Credit Facility In May 2018, FS NSW Project No 1 Finco Pty Ltd, our wholly-owned subsidiary and project financing company, entered into a term loan facility (the “Beryl Credit Facility”) with MUFG Bank, Ltd.; Société Générale, Hong Kong Branch; and Mizuho Bank, Ltd. for aggregate borrowings up to AUD 146.4 million ( $103.2 million ) for the development and construction of an 87 MW AC PV solar power plant located in New South Wales, Australia. In October 2018, the borrowing capacity on the Beryl Credit Facility was reduced to AUD 136.4 million ( $96.2 million ). Accordingly, the credit facility consists of an AUD 125.4 million ( $88.4 million ) construction loan facility, an AUD 7.0 million ( $4.9 million ) GST facility to fund certain taxes associated with the construction of the project, and an AUD 4.0 million ( $2.8 million ) letter of credit facility. Upon completion of the project’s construction, the construction loan facility will convert to a term loan facility. The term loan facility matures in May 2023, and the GST facility matures in May 2020. The credit facility is secured by pledges of the borrower’s assets, accounts, material project documents, and by the equity interests in the entity. As of December 31, 2018 , the balance outstanding on the credit facility was $77.0 million . Variable Interest Rate Risk Certain of our long-term debt agreements bear interest at prime, LIBOR, TIBOR, BBSY, or equivalent variable rates. An increase in these variable rates would increase the cost of borrowing under our Revolving Credit Facility and certain project specific debt financings. Our long-term debt borrowing rates as of December 31, 2018 were as follows: Loan Agreement December 31, 2018 Revolving Credit Facility 4.50% Luz del Norte Credit Facilities (1) Fixed rate loans at bank rate plus 3.50% Variable rate loans at 91-Day U.S. Treasury Bill Yield or LIBOR plus 3.50% Ishikawa Credit Agreement Senior loan facility at 6-month TIBOR plus 0.75% (2) Consumption tax facility at 3-month TIBOR plus 0.5% Japan Credit Facility 1-month TIBOR plus 0.5% Tochigi Credit Facility 3-month TIBOR plus 1.0% Anantapur Credit Facility INR overnight indexed swap rate plus 1.5% Tungabhadra Credit Facility INR overnight indexed swap rate plus 1.5% Beryl Credit Facility Construction loan facility at 1-month BBSY plus 1.75% (2) GST facility at 1-month BBSY plus 1.00% —————————— (1) Outstanding balance comprised of $161.1 million of fixed rate loans and $27.7 million of variable rate loans as of December 31, 2018 . (2) We have entered into interest rate swap contracts to hedge portions of these variable rates. See Note 10. “Derivative Financial Instruments” to our consolidated financial statements for additional information. During the years ended December 31, 2018 , 2017 , and 2016 , we paid $16.6 million , $10.2 million , $4.3 million , respectively, of interest related to our long-term debt arrangements. Future Principal Payments At December 31, 2018 , the future principal payments on our long-term debt were due as follows (in thousands): Total Debt 2019 $ 5,673 2020 26,935 2021 66,014 2022 12,221 2023 71,620 Thereafter 296,694 Total long-term debt future principal payments $ 479,157

Note 15. Commitments and Contin

Note 15. Commitments and Contingencies (Notes)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	15. Commitments and Contingencies Commercial Commitments During the normal course of business, we enter into commercial commitments in the form of letters of credit, bank guarantees, and surety bonds to provide financial and performance assurance to third parties. Our amended and restated Revolving Credit Facility provides us with a sub-limit of $400.0 million to issue letters of credit, subject to certain additional limits depending on the currencies of the letters of credit, at a fee based on the applicable margin for Eurocurrency revolving loans and a fronting fee. As of December 31, 2018 , we had $66.0 million in letters of credit issued under our Revolving Credit Facility, leaving $334.0 million of availability for the issuance of additional letters of credit. As of December 31, 2018 , we also had $0.6 million of bank guarantees and letters of credit under separate agreements that were posted by certain of our foreign subsidiaries and $281.1 million of letters of credit issued under three bilateral facilities, of which $44.4 million was secured with cash, leaving $157.9 million of aggregate available capacity under such agreements and facilities. We also had $57.8 million of surety bonds outstanding, leaving $658.5 million of available bonding capacity under our surety lines as of December 31, 2018 . The majority of these letters of credit, bank guarantees, and surety bonds supported our systems projects. In addition to the commercial commitments noted above, we also issued certain commercial letters of credit, also known as letters of undertaking, under our Hindupur Credit Facility as discussed in Note 14. “Debt” to our consolidated financial statements. Such commercial letters of credit represented conditional commitments on the part of the issuing financial institution to provide payment on amounts drawn in accordance with the terms of the individual documents. As part of the financing of the associated systems projects, we presented these commercial letters of credit to other financial institutions, whereby we received immediate funding, and these other financial institutions agreed to settle such letters at a future date. At the time of settlement, the balance of the commercial letters of credit would be included in the balance outstanding of the credit facility. In the periods between the receipt of cash and the subsequent settlement of the commercial letters of credit, we accrued interest on the balance or otherwise accreted any discounted value of the letters to their face value and recorded such amounts as “ Interest expense, net ” on our consolidated statements of operations. In March 2018, we completed the sale of our Hindupur projects, and the outstanding letters of credit of $43.3 million under the Hindupur Credit Facility were assumed by the customer. As of December 31, 2017 , we accrued $43.4 million for contingent obligations associated with such commercial letters of credit. These amounts were classified as “Other liabilities” on our consolidated balance sheets to align with the timing in which we expected to settle such obligations as payments under the associated credit facility. Lease Commitments We lease our corporate headquarters, administrative offices, R&D facilities, and warehouse space in the United States and international locations under noncancelable operating leases. We also lease land for the development and construction of certain systems projects and, in international locations, for our manufacturing facilities. These leases may require us to pay property taxes, common area maintenance, and certain other costs in addition to base rent. We also lease certain machinery and equipment. Future minimum payments under our operating leases were as follows as of December 31, 2018 (in thousands): Total Minimum Lease Payments 2019 $ 13,839 2020 9,031 2021 8,309 2022 7,824 2023 7,749 Thereafter 100,062 Total operating lease obligations $ 146,814 Our rent expense was $18.9 million , $22.1 million , and $24.5 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. Purchase Commitments We purchase raw materials, manufacturing equipment, construction materials, and various services from a variety of vendors. During the normal course of business, in order to manage manufacturing and construction lead times and help ensure an adequate supply of certain items, we enter into agreements with suppliers that either allow us to procure goods and services when we choose or that establish purchase requirements over the term of the agreement. In certain instances, our purchase agreements allow us to cancel, reschedule, or adjust our purchase requirements based on our business needs prior to firm orders being placed. Consequently, only a portion of our purchase commitments are firm and noncancelable or cancelable with a significant penalty. At December 31, 2018 , our obligations under such arrangements were $1.4 billion , of which $335.6 million related to capital expenditures. We expect to make $875.7 million of payments under these purchase obligations in 2019 . Product Warranties When we recognize revenue for module or system sales, we accrue liabilities for the estimated future costs of meeting our limited warranty obligations for both modules and the balance of the systems. We make and revise these estimates based primarily on the number of solar modules under warranty installed at customer locations, our historical experience with warranty claims, our monitoring of field installation sites, our internal testing and the expected future performance of our solar modules and BoS parts, and our estimated replacement costs. From time to time, we have taken remediation actions with respect to affected modules beyond our limited warranties and may elect to do so in the future, in which case we would incur additional expenses. Such potential voluntary future remediation actions beyond our limited warranty obligations may be material to our consolidated statements of operations if we commit to any such remediation actions. Product warranty activities during the years ended December 31, 2018 , 2017 , and 2016 were as follows (in thousands): 2018 2017 2016 Product warranty liability, beginning of period $ 224,274 $ 252,408 $ 231,751 Accruals for new warranties issued 14,132 23,313 35,256 Settlements (11,851 ) (11,329 ) (16,266 ) Changes in estimate of product warranty liability (5,863 ) (40,118 ) 1,667 Product warranty liability, end of period $ 220,692 $ 224,274 $ 252,408 Current portion of warranty liability $ 27,657 $ 28,767 $ 40,079 Noncurrent portion of warranty liability $ 193,035 $ 195,507 $ 212,329 During the year ended December 31, 2017, we reduced our product warranty liability by $31.3 million as a result of a reduction in the estimated replacement cost of our modules under warranty. Such change in estimate was primarily driven by continued reductions in the manufacturing cost per watt of our solar modules. We estimate our limited product warranty liability for power output and defects in materials and workmanship under normal use and service conditions based on warranty return rates of approximately 1% to 3% for modules covered under warranty, depending on the series of module technology. As of December 31, 2018 , a 1% change in estimated warranty return rates would change our module warranty liability by $74.6 million , and a 1% change in the estimated warranty return rate for BoS parts would not have a material impact on the associated warranty liability. Performance Guarantees As part of our systems business, we conduct performance testing of a system prior to substantial completion to confirm the system meets its operational and capacity expectations noted in the EPC agreement. In addition, we may provide an energy performance test during the first or second year of a system’s operation to demonstrate that the actual energy generation for the applicable period meets or exceeds the modeled energy expectation, after certain adjustments. If there is an underperformance event with regards to these tests, we may incur liquidated damages as specified in the EPC contract. In certain instances, a bonus payment may be received at the end of the applicable test period if the system performs above a specified level. As of December 31, 2018 and 2017 , we accrued $0.4 million and $2.1 million , respectively, of estimated obligations under such arrangements, which were classified as “ Other current liabilities ” in our consolidated balance sheets. As part of our O&M service offerings, we typically offer an effective availability guarantee, which stipulates that a system will be available to generate a certain percentage of total possible energy during a specific period after adjusting for factors outside of our control as the service provider, such as weather, curtailment, outages, force majeure, and other conditions that may affect system availability. Effective availability guarantees are only offered as part of our O&M services and terminate at the end of an O&M arrangement. If we fail to meet the contractual threshold for these guarantees, we may incur liquidated damages for certain lost energy under the PPA. Our O&M agreements typically contain provisions limiting our total potential losses under an agreement, including amounts paid for liquidated damages, to a percentage of O&M fees. Many of our O&M agreements also contain provisions whereby we may receive a bonus payment if system availability exceeds a separate threshold. As of December 31, 2018 and 2017 , we did not accrue any estimated obligations under our effective availability guarantees. Indemnifications In certain limited circumstances, we have provided indemnifications to customers, including project tax equity investors, under which we are contractually obligated to compensate such parties for losses they suffer resulting from a breach of a representation, warranty, or covenant or a reduction in tax benefits received, including investment tax credits. Project related tax benefits are, in part, based on guidance provided by the IRS and U.S. Treasury Department, which includes assumptions regarding the fair value of qualifying PV solar power systems. For any sales contracts that have such indemnification provisions, we initially recognize a liability under ASC 460 for the estimated premium that would be required by a guarantor to issue the same indemnity in a standalone arm’s-length transaction with an unrelated party. We typically base these estimates on the cost of insurance policies that cover the underlying risks being indemnified and may purchase such policies to mitigate our exposure to potential indemnification payments. We subsequently measure such liabilities at the greater of the initially estimated premium or the contingent liability required to be recognized under ASC 450. We recognize any indemnification liabilities as a reduction of revenue in the related transaction. After an indemnification liability is recorded, we derecognize such amount pursuant to ASC 460-10-35-2 depending on the nature of the indemnity, which derecognition typically occurs upon expiration or settlement of the arrangement, and any contingent aspects of the indemnity are accounted for in accordance with ASC 450. As of December 31, 2018 and 2017 , we accrued $3.0 million and $4.9 million of noncurrent indemnification liabilities, respectively, for tax related indemnifications. As of December 31, 2017 , we also accrued $2.9 million of current indemnification liabilities for such matters. As of December 31, 2018 , the maximum potential amount of future payments under our tax related and other indemnifications was $125.3 million , and we held insurance policies allowing us to recover up to $84.9 million of potential amounts paid under the indemnifications covered by the policies. Contingent Consideration As part of our prior acquisition of Enki, we agreed to pay additional consideration to the selling shareholders contingent upon the achievement of certain production and module performance milestones. See Note 5. “Business Acquisitions” to our consolidated financial statements for further discussion of this acquisition. In October 2018, we paid the remaining consideration of $3.5 million to the selling shareholders as a result of the achievement of the second performance milestone. As of December 31, 2017 , we accrued $1.8 million of current liabilities for our contingent obligations associated with the Enki acquisition based on their estimated fair values and the expected timing of payment. We continually seek to make additions to our advanced-stage project pipeline by actively developing our early-to-mid-stage project pipeline and by pursuing opportunities to acquire projects at various stages of development. In connection with such project acquisitions, we may agree to pay additional amounts to project sellers upon the achievement of certain milestones, such as obtaining a PPA, obtaining financing, or selling the project to a new owner. We recognize a project acquisition contingent liability when we determine that such a liability is both probable and reasonably estimable, and the carrying amount of the related project asset is correspondingly increased. As of December 31, 2018 and 2017 , we accrued $0.7 million and $4.4 million of current liabilities, respectively, and $2.3 million and $3.2 million of long-term liabilities, respectively, for project related contingent obligations. Any future differences between the acquisition-date contingent obligation estimate and the ultimate settlement of the obligation are recognized as an adjustment to the project asset, as contingent payments are considered direct and incremental to the underlying value of the related project. Legal Proceedings Class Action On March 15, 2012, a purported class action lawsuit titled Smilovits v. First Solar, Inc., et al., Case No. 2:12-cv-00555-DGC, was filed in the United States District Court for the District of Arizona (hereafter “Arizona District Court”) against the Company and certain of our current and former directors and officers. The complaint was filed on behalf of persons who purchased or otherwise acquired the Company’s publicly traded securities between April 30, 2008 and February 28, 2012 (the “Class Action”). The complaint generally alleges that the defendants violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 by making false and misleading statements regarding the Company’s financial performance and prospects. The action includes claims for damages, including interest, and an award of reasonable costs and attorneys’ fees to the putative class. The Company believes it has meritorious defenses and will vigorously defend this action. On July 23, 2012, the Arizona District Court issued an order appointing as lead plaintiffs in the Class Action the Mineworkers’ Pension Scheme and British Coal Staff Superannuation Scheme (collectively, the “Pension Schemes”). The Pension Schemes filed an amended complaint on August 17, 2012, which contains similar allegations and seeks similar relief as the original complaint. Defendants filed a motion to dismiss on September 14, 2012. On December 17, 2012, the court denied defendants’ motion to dismiss. On October 8, 2013, the Arizona District Court granted the Pension Schemes’ motion for class certification and certified a class comprised of all persons who purchased or otherwise acquired publicly traded securities of the Company between April 30, 2008 and February 28, 2012 and were damaged thereby, excluding defendants and certain related parties. Merits discovery closed on February 27, 2015. Defendants filed a motion for summary judgment on March 27, 2015. On August 11, 2015, the Arizona District Court granted defendants’ motion in part and denied it in part, and certified an issue for immediate appeal to the Ninth Circuit Court of Appeals (the “Ninth Circuit”). First Solar filed a petition for interlocutory appeal with the Ninth Circuit, and that petition was granted on November 18, 2015. On May 20, 2016, the Pension Schemes moved to vacate the order granting the petition, dismiss the appeal, and stay the merits briefing schedule. On December 13, 2016, the Ninth Circuit denied the Pension Schemes’ motion. On January 31, 2018, the Ninth Circuit issued an opinion affirming the Arizona District Court’s order denying in part defendants’ motion for summary judgment. On March 16, 2018, First Solar filed a petition for panel rehearing or rehearing en banc with the Ninth Circuit. On May 7, 2018, the Ninth Circuit denied defendants’ petition. On August 6, 2018, defendants filed a petition for writ of certiorari to the U.S. Supreme Court. The Court has not yet ruled on that petition. Meanwhile, in the Arizona District Court, expert discovery was completed on February 5, 2019. The Arizona District Court vacated the previously scheduled trial date and all other deadlines until the outcome of the certiorari petition is clear. This lawsuit asserts claims that, if resolved against us, could give rise to substantial damages, and an unfavorable outcome or settlement may result in a significant monetary judgment or award against us or a significant monetary payment by us, and could have a material adverse effect on our business, financial condition, and results of operations. Even if this lawsuit is not resolved against us, the costs of defending the lawsuit and of any settlement may be significant. These costs would likely exceed the dollar limits of our insurance policies or may not be covered by our insurance policies. Given the uncertainties of trial, at this time we are not in a position to assess the likelihood of any potential loss or adverse effect on our financial condition or to estimate the range of potential loss, if any. Opt-Out Action On June 23, 2015, a suit titled Maverick Fund, L.D.C. v. First Solar, Inc., et al., Case No. 2:15-cv-01156-ROS, was filed in Arizona District Court by putative stockholders that opted out of the Class Action. The complaint names the Company and certain of our current and former directors and officers as defendants, and alleges that the defendants violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, and violated state law, by making false and misleading statements regarding the Company’s financial performance and prospects. The action includes claims for recessionary and actual damages, interest, punitive damages, and an award of reasonable attorneys’ fees, expert fees, and costs. The Company believes it has meritorious defenses and will vigorously defend this action. First Solar and the individual defendants filed a motion to dismiss the complaint on July 16, 2018. On November 27, 2018, the Court granted defendants’ motion to dismiss the plaintiffs’ negligent misrepresentation claim under state law, but otherwise denied defendants’ motion. This action is still in the initial stages, and there has been no discovery. Accordingly, at this time we are not in a position to assess the likelihood of any potential loss or adverse effect on our financial condition or to estimate the range of potential loss, if any. Derivative Actions On July 16, 2013, a derivative complaint was filed in the Superior Court of Arizona, Maricopa County, titled Bargar, et al. v. Ahearn, et al., Case No. CV2013-009938, by a putative stockholder against certain current and former directors and officers of the Company (“Bargar”). The complaint generally alleges that the defendants caused or allowed false and misleading statements to be made concerning the Company’s financial performance and prospects. The action includes claims for, among other things, breach of fiduciary duties, insider trading, unjust enrichment, and waste of corporate assets. By court order on October 3, 2013, the Superior Court of Arizona, Maricopa County granted the parties’ stipulation to defer defendants’ response to the complaint pending resolution of the Class Action or expiration of a stay issued in certain consolidated derivative actions in the Arizona District Court. On November 5, 2013, the matter was placed on the court’s inactive calendar. The parties have jointly sought and obtained multiple requests to continue the stay in this action. Most recently, on November 9, 2018, the court entered an order continuing the stay until March 29, 2019. The Company believes that the plaintiff in the Bargar derivative action lacks standing to pursue litigation on behalf of First Solar. The Bargar derivative action is still in the initial stages and there has been no discovery. Accordingly, at this time we are not in a position to assess the likelihood of any potential loss or adverse effect on our financial condition or to estimate the range of potential loss, if any. Other Matters and Claims We are party to other legal matters and claims in the normal course of our operations. While we believe the ultimate outcome of such other matters and claims will not have a material adverse effect on our financial position, results of operations, or cash flows, the outcome of such matters and claims is not determinable with certainty, and negative outcomes may adversely affect us.

Note 16. Revenue from Contracts

Note 16. Revenue from Contracts with Customers (Notes)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers [Text Block]	16. Revenue from Contracts with Customers The following table represents a disaggregation of revenue from contracts with customers for the years ended December 31, 2018 , 2017 , and 2016 along with the reportable segment for each category (in thousands): Category Segment 2018 2017 2016 Solar modules Modules $ 502,001 $ 806,398 $ 675,453 Solar power systems Systems 1,244,175 1,927,122 1,131,961 EPC services Systems 347,560 45,525 892,814 O&M services Systems 103,186 101,024 93,476 Module plus Systems — 3,236 84,926 Energy generation (1) Systems 47,122 58,019 25,933 Net sales $ 2,244,044 $ 2,941,324 $ 2,904,563 —————————— (1) During the years ended December 31, 2017 and 2016 , the majority of energy generated and sold by our PV solar power systems was accounted for under ASC 840 consistent with the classification of the associated PPAs. We recognize revenue for module sales at a point in time following the transfer of control of the modules to the customer, which typically occurs upon shipment or delivery depending on the terms of the underlying contracts. Such contracts may contain provisions that require us to make liquidated damage payments to the customer if we fail to deliver modules by scheduled dates. We recognize these liquidated damages as a reduction of revenue in the period we transfer control of the modules to the customer. We generally recognize revenue for sales of solar power systems and/or EPC services over time using cost based input methods, in which significant judgment is required to evaluate assumptions including the amount of net contract revenues and the total estimated costs to determine our progress towards contract completion and to calculate the corresponding amount of revenue to recognize. If the estimated total costs on any contract are greater than the net contract revenues, we recognize the entire estimated loss in the period the loss becomes known. The cumulative effect of revisions to estimates related to net contract revenues or costs to complete contracts are recorded in the period in which the revisions to estimates are identified and the amounts can be reasonably estimated. Changes in estimates for sales of systems and EPC services occur for a variety of reasons, including but not limited to (i) construction plan accelerations or delays, (ii) module cost forecast changes, (iii) cost related change orders, or (iv) changes in other information used to estimate costs. Changes in estimates may have a material effect on our consolidated statements of operations. The following table outlines the impact on revenue of net changes in estimated transaction prices and input costs for systems related sales contracts (both increases and decreases) for the years ended December 31, 2018 , 2017 , and 2016 as well as the number of projects that comprise such changes. For purposes of the table, we only include projects with changes in estimates that have a net impact on revenue of at least $1.0 million during the periods presented with the exception of the sales and use tax matter described below, for which the aggregate change in estimate has been presented. Also included in the table is the net change in estimate as a percentage of the aggregate revenue for such projects. 2018 2017 2016 Number of projects (1) 24 5 12 Increase (decrease) in revenue from net changes in transaction prices (in thousands) (1) $ 63,361 $ 3,579 $ (67,292 ) Increase in revenue from net changes in input cost estimates (in thousands) 1,548 5,047 164,920 Net increase in revenue from net changes in estimates (in thousands) $ 64,909 $ 8,626 $ 97,628 Net change in estimate as a percentage of aggregate revenue 0.6 % 0.6 % 1.6 % —————————— (1) During the year ended December 31, 2018 , we settled a tax examination with the state of California regarding several matters, including certain sales and use tax payments due under lump sum EPC contracts. Accordingly, we revised our estimates of sales and use taxes due for projects in the state of California, which affected the estimated transaction prices for such contracts, and recorded an increase to revenue of $54.6 million . The following table reflects the changes in our contract assets, which we classify as “Accounts receivable, unbilled” or “Retainage,” and our contract liabilities, which we classify as “Deferred revenue,” for the year ended December 31, 2018 (in thousands): 2018 2017 Change Accounts receivable, unbilled $ 441,666 $ 172,594 Retainage 16,500 2,014 Accounts receivable, unbilled and retainage $ 458,166 $ 174,608 $ 283,558 162 % Deferred revenue (1) $ 177,769 $ 145,073 $ 32,696 23 % —————————— (1) Includes $48.0 million and $63.3 million of long-term deferred revenue classified as “ Other liabilities ” on our consolidated balance sheets as of December 31, 2018 and 2017 , respectively. Accounts receivable, unbilled represents a contract asset for revenue that has been recognized in advance of billing the customer, which is common for long-term construction contracts. Billing requirements vary by contract but are generally structured around the completion of certain construction milestones. Some of our EPC contracts for systems we build may also contain retainage provisions. Retainage represents a contract asset for the portion of the contract price earned by us for work performed, but held for payment by the customer as a form of security until we reach certain construction milestones. When we receive consideration, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a sales contract, we record deferred revenue, which represents a contract liability. Such deferred revenue typically results from billings in excess of costs incurred on long-term construction contracts and advance payments received on sales of solar modules. For the year ended December 31, 2018 , our contract assets increased by $283.6 million primarily due to certain unbilled receivables associated with ongoing construction activities at the Willow Springs and California Flats projects and the completion of the sale of the Manildra project. For the year ended December 31, 2018 , our contract liabilities increased by $32.7 million primarily as a result of advance payments received for sales of solar modules, partially offset by revenue recognition for certain EPC projects in Florida, for which we received a portion of the proceeds in 2017, and the completion of the sale of certain Japan projects, for which we collected the proceeds in 2017. During the years ended December 31, 2018 and 2017 , we recognized revenue of $128.7 million and $308.6 million , respectively, that was included in the corresponding contract liability balance at the beginning of the periods. The following table represents our remaining performance obligations as of December 31, 2018 for sales of solar power systems, including uncompleted sold projects, projects under sales contracts subject to conditions precedent, and EPC agreements for partner developed projects that we are constructing or expect to construct. Such table excludes remaining performance obligations for any sales arrangements that had not fully satisfied the criteria to be considered a contract with a customer pursuant to the requirements of ASC 606. We expect to recognize $0.7 billion of revenue for such contracts through the later of the substantial completion or the closing dates of the projects. Project/Location Project Size in MW AC Revenue Category EPC Contract/Partner Developed Project Expected Year Revenue Recognition Will Be Completed % of Revenue Recognized Phoebe, Texas 250 EPC Innergix Renewable Energy 2019 12% GA Solar 4, Georgia (1) 200 Solar power systems Origis Energy USA 2020 11% Rosamond, California 150 Solar power systems Clearway Energy Group 2019 57% Willow Springs, California 100 Solar power systems D.E. Shaw Renewable Investments 2019 96% Grange Hall, Florida 61 EPC Tampa Electric Company 2019 98% Peace Creek, Florida 55 EPC Tampa Electric Company 2019 70% Troy Solar, Indiana 51 EPC Southern Indiana Gas and Electric Company 2020 —% Lake Hancock, Florida 50 EPC Tampa Electric Company 2019 34% Total 917 —————————— (1) Previously known as the Twiggs County Solar project As of December 31, 2018 , we had entered into contracts with customers for the future sale of 8.9 GW DC of solar modules for an aggregate transaction price of $3.2 billion . We expect to recognize such amounts as revenue through 2022 as we transfer control of the modules to the customers. As of December 31, 2018 , we had also entered into long-term O&M contracts covering approximately 8 GW DC of utility-scale PV solar power systems. We expect to recognize $0.5 billion of revenue during the noncancelable term of these O&M contracts over a weighted-average period of 11.5 years .

Note 17. Stockholders' Equity (

Note 17. Stockholders' Equity (Notes)	12 Months Ended
	Dec. 31, 2018
Class of Stock Disclosures [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	17. Stockholders’ Equity Preferred Stock We have authorized 30,000,000 shares of undesignated preferred stock, $0.001 par value, none of which was issued and outstanding at December 31, 2018 and 2017 . Our board of directors is authorized to determine the rights, preferences, and restrictions on any series of preferred stock that we may issue. Common Stock We have authorized 500,000,000 shares of common stock, $0.001 par value, of which 104,885,261 and 104,468,460 shares were issued and outstanding at December 31, 2018 and 2017 , respectively. Each share of common stock is entitled to a single vote. We have not declared or paid any dividends through December 31, 2018 .

Note 18. Share-Based Compensati

Note 18. Share-Based Compensation (Notes)	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	18. Share-Based Compensation The following table presents share-based compensation expense recognized in our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Cost of sales $ 6,422 $ 6,809 $ 7,598 Selling, general and administrative 21,646 22,165 17,830 Research and development 5,714 5,740 3,284 Production start-up 372 407 — Total share-based compensation expense $ 34,154 $ 35,121 $ 28,712 The following table presents share-based compensation expense by type of award for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Restricted and performance stock units $ 32,223 $ 32,309 $ 25,076 Unrestricted stock 1,637 1,757 1,677 Stock purchase plan — 394 1,332 33,860 34,460 28,085 Net amount released from inventory 294 661 627 Total share-based compensation expense $ 34,154 $ 35,121 $ 28,712 Share-based compensation expense capitalized in inventory was $1.8 million and $2.1 million as of December 31, 2018 and 2017 , respectively. As of December 31, 2018 , we had $37.6 million of unrecognized share-based compensation expense related to unvested restricted and performance stock units, which we expect to recognize over a weighted-average period of approximately 1.1 years . During the years ended December 31, 2018 , 2017 , and 2016 , we recognized an income tax benefit in our statement of operations of $9.9 million , $6.2 million , and $32.9 million , respectively, related to share-based compensation expense, including any excess tax benefits or deficiencies. We authorize our transfer agent to issue new shares, net of shares withheld for taxes as appropriate, for the vesting of restricted and performance stock units or grants of unrestricted stock. Share-Based Compensation Plans During the year ended December 31, 2015, we adopted our 2015 Omnibus Incentive Compensation Plan (“the 2015 Omnibus Plan”), under which directors, officers, employees, and consultants of First Solar (including any of its subsidiaries) are eligible to participate in various forms of share-based compensation. The 2015 Omnibus Plan is administered by the compensation committee of our board of directors (or any other committee designated by our board of directors), which is authorized to, among other things, determine the recipients of grants, the exercise price, and the vesting schedule of any awards made under the 2015 Omnibus Plan. Our board of directors may amend, modify, or terminate the 2015 Omnibus Plan without the approval of our stockholders, except for amendments that would increase the maximum number of shares of our common stock available for awards under the 2015 Omnibus Plan, increase the maximum number of shares of our common stock that may be delivered by incentive stock options, or modify the requirements for participation in the 2015 Omnibus Plan. The 2015 Omnibus Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted shares, restricted stock units, performance units, cash incentive awards, performance compensation awards, and other equity-based and equity-related awards. In addition, the shares underlying any forfeited, expired, terminated, or canceled awards, or shares surrendered as payment for taxes required to be withheld, become available for new award grants. We may not grant awards under the 2015 Omnibus Plan after 2025 , which is the tenth anniversary of the 2015 Omnibus Plan’s approval by our stockholders. As of December 31, 2018 , we had 2,960,873 shares available for future issuance under the 2015 Omnibus Plan. Restricted and Performance Stock Units We issue shares to the holders of restricted stock units on the date the restricted units vest. The majority of shares issued are net of applicable withholding taxes, which we pay on behalf of our associates. As a result, the actual number of shares issued will be less than the number of restricted stock units granted. Prior to vesting, restricted stock units do not have dividend equivalent rights or voting rights, and the shares underlying the restricted stock units are not considered issued and outstanding. In February 2017, the compensation committee of our board of directors approved a long-term incentive program for key executive officers and associates. The program is intended to incentivize retention of our key executive talent, provide a smooth transition from our former key senior talent equity performance program (“KSTEPP”), and align the interests of executive management and stockholders. Specifically, the program consists of (i) performance stock units to be earned over an approximately three-year performance period beginning in March 2017 and (ii) stub-year grants of separate performance stock units to be earned over an approximately two-year performance period also beginning in March 2017. Vesting of the March 2017 performance stock units is contingent upon the relative attainment of target cost per watt and operating expense metrics. In April 2018, in continuation of our long-term incentive program for key executive officers and associates, the compensation committee of our board of directors approved additional grants of performance stock units to be earned over an approximately three-year performance period beginning in May 2018. Vesting of the May 2018 performance stock units is contingent upon the relative attainment of target gross margin, operating expense, and contracted revenue metrics. Vesting of performance stock units is also contingent upon the employment of program participants through the applicable vesting dates, with limited exceptions in case of death, disability, a qualifying retirement, or a change-in-control of First Solar. Performance stock units were included in the computation of diluted net income per share for the years ended December 31, 2018 and 2017 based on the number of shares that would be issuable if the end of the reporting period were the end of the contingency period. Our board of directors previously approved and adopted the KSTEPP, a performance unit program under our prior 2010 Omnibus Incentive Compensation Plan applicable to our senior executives. The KSTEPP rewarded achievement of certain performance objectives aligned to the success of our long-term strategic plans. Such performance objectives included KSTEPP adjusted operating income, sales in key geographic markets, and cash adjusted return on invested capital. The KSTEPP awards were designed so that the attainment of the performance criteria required for full or partial vesting would be attained over time. In July 2016, the compensation committee of our board of directors certified the achievement of the full KSTEPP vesting conditions for the rolling annual period ended June 30, 2016. Accordingly, the remaining two-thirds of each KSTEPP award vested in 2016, and each KSTEPP participant received one share of common stock for each vested KSTEPP performance unit, net of any forfeitures. The following is a summary of our restricted stock unit activity, including performance stock unit activity, for the year ended December 31, 2018 : Number of Shares Weighted-Average Grant-Date Fair Value Unvested restricted stock units at December 31, 2017 2,302,906 $ 38.55 Restricted stock units granted (1) 739,855 67.44 Restricted stock units vested (490,682) 44.46 Restricted stock units forfeited (77,792) 51.04 Unvested restricted stock units at December 31, 2018 2,474,287 $ 45.63 —————————— (1) Restricted stock units granted include the maximum amount of performance stock units available for issuance under our long-term incentive program for key executive officers and associates. The actual number of shares to be issued will depend on the relative attainment of the performance metrics described above. We estimate the fair value of our restricted stock unit awards based on our stock price at the grant date. For the years ended December 31, 2017 and 2016 , the weighted-average grant-date fair value for restricted stock units granted in such years was $32.81 and $59.64 , respectively. The total fair value of restricted stock units vested during 2018 , 2017 , and 2016 was $32.2 million , $14.1 million , and $131.0 million , respectively. Unrestricted Stock During the years ended December 31, 2018 , 2017 , and 2016 , we awarded 31,190 ; 42,773 ; and 38,429 , respectively, of fully vested, unrestricted shares of our common stock to the independent members of our board of directors. Accordingly, we recognized $1.6 million , $1.8 million , and $1.7 million of share-based compensation expense for these awards during the years ended December 31, 2018 , 2017 , and 2016 , respectively. Stock Purchase Plan Our shareholders approved our stock purchase plan for employees in June 2010. The plan allows employees to purchase our common stock through payroll withholdings over a six-month offering period at a discount from the closing share price on the last day of the offering period. In April 2017, we amended our stock purchase plan to reduce the purchase discount from 15% to 4% . Accordingly, the plan is considered noncompensatory and no longer results in the recognition of share-based compensation expense.

Note 19. Income Taxes (Notes)

Note 19. Income Taxes (Notes)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	19. Income Taxes In December 2017, the United States enacted the Tax Act, which significantly revised U.S. tax law by, among other things, lowering the statutory federal corporate income tax rate from 35% to 21% effective January 1, 2018, eliminating certain deductions, imposing a transition tax on certain accumulated earnings and profits of foreign corporate subsidiaries, introducing new tax regimes, and changing how foreign earnings are subject to U.S. tax. In December 2017, the SEC issued Staff Accounting Bulletin No. 118 to (i) clarify certain aspects of accounting for income taxes under ASC 740 in the reporting period the Tax Act was signed into law when information is not yet available or complete and (ii) provide a measurement period up to one year to complete the accounting for the Tax Act. We completed our accounting for the Tax Act in the fourth quarter of 2018 and recorded certain adjustments to our provisional tax expenses. As a result of the Tax Act, we remeasured certain deferred tax assets and liabilities based on the tax rate applicable to when the temporary differences are expected to reverse in the future, which is generally 21% , and recorded a provisional tax expense of $6.6 million for the year ended December 31, 2017 . During the year ended December 31, 2018 , we reduced our provisional tax expense for the remeasurement of deferred tax assets and liabilities by $2.3 million . The transition tax of the Tax Act was based on our total post-1986 foreign earnings and profits, which we previously deferred from U.S. income taxes under prior tax law. During the year ended December 31, 2017 , we recorded a provisional transition tax expense of $401.5 million , which we reduced by $8.1 million during the year ended December 31, 2018 . We elected to pay the transition tax over an eight-year period, and our outstanding transition tax liability was $81.2 million as of December 31, 2018 after the utilization of certain tax credits and tax losses and our initial installment payment in 2018. Our measurement period adjustments for the remeasurement of deferred tax assets and liabilities and the transition tax reduced our effective tax rate by 9.2% for the year ended December 31, 2018 . Although we continue to evaluate our plans for the reinvestment or repatriation of unremitted foreign earnings, we expect to indefinitely reinvest the earnings of our foreign subsidiaries to fund our international operations, with the exception of our subsidiaries in Canada and Germany. Accordingly, we have not recorded any provision for additional U.S. or foreign withholding taxes related to the outside basis differences of our foreign subsidiaries in which we expect to indefinitely reinvest their earnings. The Tax Act subjects a U.S. shareholder to tax on global intangible low-taxed income (“GILTI”) earned by foreign corporate subsidiaries. Accordingly, we record taxes due on future U.S. inclusions in taxable income related to GILTI as a current-period expense when incurred (i.e., “period cost method”). Such policy election did not result in any estimated GILTI inclusions in our effective tax rate for the year ended December 31, 2018 . The base erosion anti-abuse tax (“BEAT”) provisions of the Tax Act impose a minimum tax related to certain deductible payments made to related foreign persons. In addition, the foreign-derived intangible income (“FDII”) provision of the Tax Act allows a U.S. corporation to deduct 37.5% of its foreign-derived intangible income. The BEAT and FDII provisions of the Tax Act did not have a material impact on our income tax expense for the year ended December 31, 2018 . The U.S. and non-U.S. components of our income or loss before income taxes for the years ended December 31, 2018 , 2017 , and 2016 were as follows (in thousands): 2018 2017 2016 U.S. income $ (49,353 ) $ (22,868 ) $ (426,791 ) Non-U.S. income 162,500 224,983 (110,460 ) Income (loss) before taxes and equity in earnings $ 113,147 $ 202,115 $ (537,251 ) The components of our income tax expense or benefit for the years ended December 31, 2018 , 2017 , and 2016 were as follows (in thousands): 2018 2017 2016 Current (benefit) expense: Federal $ (44,267 ) $ 116,956 $ (14,389 ) State (13,568 ) 3,009 1,303 Foreign 8,788 11,099 (29,009 ) Total current (benefit) expense (49,047 ) 131,064 (42,095 ) Deferred expense: Federal 31,530 226,570 90,319 State 2,387 5,335 (9,536 ) Foreign 18,571 9,027 (15,521 ) Total deferred expense 52,488 240,932 65,262 Total income tax expense $ 3,441 $ 371,996 $ 23,167 Our Malaysian subsidiary has been granted a long-term tax holiday that expires in 2027 . The tax holiday, which generally provides for a full exemption from Malaysian income tax, is conditional upon our continued compliance with meeting certain employment and investment thresholds, which we are currently in compliance with and expect to continue to comply with through the expiration of the tax holiday in 2027 . Our income tax results differed from the amount computed by applying the relevant U.S. statutory federal corporate income tax rate to our income or loss before income taxes for the following reasons for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Tax Percent Tax Percent Tax Percent Statutory income tax expense (benefit) $ 23,761 21.0 % $ 70,740 35.0 % $ (188,038 ) 35.0 % Provisional effect of Tax Act — — % 408,090 201.9 % — — % Changes in valuation allowance 19,064 16.8 % 9,534 4.7 % 2,412 (0.4 )% Foreign tax rate differential 14,117 12.5 % (22,048 ) (10.9 )% 6,833 (1.3 )% State tax, net of federal benefit (7,580 ) (6.7 )% 4,397 2.2 % (8,655 ) 1.6 % Non-deductible expenses 4,636 4.1 % 2,703 1.3 % 324 — % Share-based compensation (2,105 ) (1.9 )% 1,161 0.6 % (23,283 ) 4.3 % Change in tax contingency (6,273 ) (5.5 )% 959 0.5 % (34,541 ) 6.4 % Foreign dividend income 16,570 14.6 % 540 0.3 % 248,013 (46.2 )% Goodwill — — % — — % 22,468 (4.2 )% Tax credits (8,431 ) (7.5 )% (18,445 ) (9.1 )% (15,435 ) 2.9 % Return to provision adjustments (25,307 ) (22.3 )% (35,191 ) (17.4 )% 11,757 (2.2 )% Effect of tax holiday (26,277 ) (23.2 )% (46,643 ) (23.1 )% 4,640 (0.9 )% Other 1,266 1.1 % (3,801 ) (1.9 )% (3,328 ) 0.7 % Reported income tax expense $ 3,441 3.0 % $ 371,996 184.1 % $ 23,167 (4.3 )% During the years ended December 31, 2018 , 2017 , and 2016 , we made net tax payments of $58.8 million , $1.2 million , and $1.9 million , respectively. In May 2017, the U.S. federal income tax authority accepted our election to classify certain of our German subsidiaries as disregarded entities of First Solar, Inc. effective January 1, 2017. Accordingly, we recorded an estimated benefit of $42.1 million through the tax provision to establish a deferred tax asset for excess foreign tax credits generated as a result of the associated election. In July 2016, we received a letter from a foreign tax authority confirming our residency status in that jurisdiction. In accordance with the letter, we reversed a liability associated with an uncertain tax position related to the income of a foreign subsidiary. Accordingly, we recorded a benefit of $35.4 million through the tax provision from the reversal of such liability. Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities calculated under U.S. GAAP and the amounts calculated for preparing our income tax returns. The items that gave rise to our deferred taxes as of December 31, 2018 and 2017 were as follows (in thousands): 2018 2017 Deferred tax assets: Net operating losses $ 108,149 $ 124,281 Accrued expenses 55,754 62,345 Property, plant and equipment 18,796 35,104 Compensation 18,564 9,442 Goodwill 9,223 12,140 Long-term contracts 4,967 4,554 Inventory 4,079 7,601 Capitalized interest 2,948 — Equity in earnings 2,693 — Deferred expenses 2,165 2,057 Other 17,373 12,584 Deferred tax assets, gross 244,711 270,108 Valuation allowance (159,546 ) (143,818 ) Deferred tax assets, net of valuation allowance 85,165 126,290 Deferred tax liabilities: Restricted investments and derivatives (7,586 ) (10,680 ) Acquisition accounting / basis difference (5,420 ) (5,880 ) Investments in foreign subsidiaries (4,425 ) (9,555 ) Equity in earnings — (40,339 ) Capitalized interest — (1,722 ) Other (3,093 ) (7,541 ) Deferred tax liabilities (20,524 ) (75,717 ) Net deferred tax assets and liabilities $ 64,641 $ 50,573 We use the deferral method of accounting for investment tax credits under which the credits are recognized as reductions in the carrying value of the related assets. The use of the deferral method also results in a basis difference from the recognition of a deferred tax asset and an immediate income tax benefit for the future tax depreciation of the related assets. Such basis differences are accounted for pursuant to the income statement method. Changes in the valuation allowance against our deferred tax assets were as follows during the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Valuation allowance, beginning of year $ 143,818 $ 123,936 $ 121,524 Additions 29,359 27,591 13,933 Reversals (13,631 ) (7,709 ) (11,521 ) Valuation allowance, end of year $ 159,546 $ 143,818 $ 123,936 We maintained a valuation allowance of $159.5 million and $143.8 million as of December 31, 2018 and 2017 , respectively, against certain of our deferred tax assets, as it is more likely than not that such amounts will not be fully realized. During the year ended December 31, 2018 , the valuation allowance increased by $15.7 million primarily due to current year operating losses in certain jurisdictions and an increase in deferred tax assets with a full valuation allowance due to a change in foreign exchange rates. These increases were partially offset by the release of valuation allowances in jurisdictions with current year operating income. As of December 31, 2018 , we had federal and aggregate state net operating loss carryforwards of $10.3 million and $72.9 million , respectively. As of December 31, 2017 , we had federal and aggregate state net operating loss carryforwards of $11.7 million and $20.3 million , respectively. If not used, the federal net operating loss carryforwards incurred prior to 2018 will begin to expire in 2030 , and the state net operating loss carryforwards will begin to expire in 2029 . Federal net operating losses arising in tax years beginning in 2018 may be carried forward indefinitely but may not be carried back, and the associated deduction is limited to 80% of taxable income. The utilization of our net operating loss carryforwards is also subject to an annual limitation under Section 382 of the Internal Revenue Code due to changes in ownership. Based on our analysis, we do not believe such limitation will impact our realization of the net operating loss carryforwards as we anticipate utilizing them prior to expiration. During the year ended December 31, 2017 , we utilized substantially all of our gross federal and state R&D credit carryforwards, U.S. foreign tax credit carryforwards, and investment tax credits to reduce our transition tax liability. A reconciliation of the beginning and ending amount of liabilities associated with uncertain tax positions for the years ended December 31, 2018 , 2017 , and 2016 is as follows (in thousands): 2018 2017 2016 Unrecognized tax benefits, beginning of year $ 84,173 $ 89,256 $ 141,755 Increases related to prior year tax positions — 3,827 — Decreases related to prior year tax positions (2,979 ) — (6,119 ) Decreases from lapse in statute of limitations (10,704 ) (11,840 ) (14,421 ) Decreases relating to settlements with authorities — (2,494 ) (35,416 ) Increases related to current tax positions 1,703 5,424 3,457 Unrecognized tax benefits, end of year $ 72,193 $ 84,173 $ 89,256 If recognized, $70.4 million of unrecognized tax benefits, excluding interest and penalties, would reduce our annual effective tax rate. Due to the uncertain and complex application of tax laws and regulations, it is possible that the ultimate resolution of uncertain tax positions may result in liabilities that could be materially different from these estimates. In such an event, we will record additional tax expense or benefit in the period in which such resolution occurs. Our policy is to recognize any interest and penalties that we may incur related to our tax positions as a component of income tax expense. During the years ended December 31, 2018 and 2017 , we recognized interest and penalties of $5.3 million and $5.5 million , respectively, related to unrecognized tax benefits. We did not recognize any interest or penalties related to unrecognized tax benefits during 2016 . It is reasonably possible that less than $0.1 million of uncertain tax positions will be recognized within the next 12 months due to the expiration of the statute of limitations associated with such positions. We are subject to audit by federal, state, local, and foreign tax authorities. During the year ended December 31, 2017 , we settled certain examinations in Germany, which resulted in a discrete tax expense of $2.5 million . We are currently under examination in Chile, India, Malaysia, Singapore, and the state of California. We believe that adequate provisions have been made for any adjustments that may result from tax examinations. However, the outcome of tax examinations cannot be predicted with certainty. If any issues addressed by our tax examinations are not resolved in a manner consistent with our expectations, we could be required to adjust our provision for income taxes in the period such resolution occurs. The following table summarizes the tax years that are either currently under audit or remain open and subject to examination by the tax authorities in the most significant jurisdictions in which we operate: Tax Years Australia 2013 - 2017 India 2013 - 2018 Malaysia 2013 - 2017 United States 2008 - 2009; 2013 - 2017 In certain of the jurisdictions noted above, we operate through more than one legal entity, each of which has different open years subject to examination. The table above presents the open years subject to examination for the most material of the legal entities in each jurisdiction. Additionally, tax years are not closed until the statute of limitations in each jurisdiction expires. In the jurisdictions noted above, the statute of limitations can extend beyond the open years subject to examination.

Note 20. Net Income (Loss) Per

Note 20. Net Income (Loss) Per Share (Notes)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Net Income (Loss) per Share	20. Net Income (Loss) per Share Basic net income (loss) per share is computed by dividing net income (loss) by the weighted-average number of common shares outstanding for the period. Diluted net income per share is computed giving effect to all potentially dilutive common shares, including restricted and performance stock units and stock purchase plan shares, unless there is a net loss for the period. In computing diluted net income per share, we utilize the treasury stock method. The calculation of basic and diluted net income (loss) per share for the years ended December 31, 2018 , 2017 , and 2016 was as follows (in thousands, except per share amounts): 2018 2017 2016 Basic net income (loss) per share Numerator: Net income (loss) $ 144,326 $ (165,615 ) $ (416,112 ) Denominator: Weighted-average common shares outstanding 104,745 104,328 102,866 Diluted net income (loss) per share Denominator: Weighted-average common shares outstanding 104,745 104,328 102,866 Effect of restricted and performance stock units and stock purchase plan shares 1,368 — — Weighted-average shares used in computing diluted net income (loss) per share 106,113 104,328 102,866 Net income (loss) per share: Basic $ 1.38 $ (1.59 ) $ (4.05 ) Diluted $ 1.36 $ (1.59 ) $ (4.05 ) The following table summarizes the potential shares of common stock that were excluded from the computation of diluted net income per share for the years ended December 31, 2018 , 2017 , and 2016 as such shares would have had an anti-dilutive effect (in thousands): 2018 2017 2016 Anti-dilutive shares 299 1,021 753

Note 21. Accumulated Other Comp

Note 21. Accumulated Other Comprehensive (Loss) Income (Notes)	12 Months Ended
	Dec. 31, 2018
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive (Loss) Income	21. Accumulated Other Comprehensive (Loss) Income The following table presents the changes in accumulated other comprehensive (loss) income, net of tax, for the year ended December 31, 2018 (in thousands): Foreign Currency Translation Adjustment Unrealized Gain (Loss) on Marketable Securities and Restricted Investments Unrealized Gain (Loss) on Derivative Instruments Total Balance as of December 31, 2017 $ (65,346 ) $ 68,388 $ (783 ) $ 2,259 Other comprehensive loss before reclassifications (1,034 ) (6,077 ) (3,760 ) (10,871 ) Amounts reclassified from accumulated other comprehensive (loss) income — (55,405 ) 6,812 (48,593 ) Net tax effect — 3,735 (996 ) 2,739 Net other comprehensive (loss) income (1,034 ) (57,747 ) 2,056 (56,725 ) Balance as of December 31, 2018 $ (66,380 ) $ 10,641 $ 1,273 $ (54,466 ) The following table presents the pretax amounts reclassified from accumulated other comprehensive (loss) income into our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Comprehensive Income Components Income Statement Line Item Amounts Reclassified for the Year Ended December 31, 2018 2017 2016 Unrealized gain on marketable securities and restricted investments Other income, net $ 55,405 $ 49 $ 41,633 Unrealized (loss) gain on derivative contracts: Foreign exchange forward contracts Net sales (1,698 ) — — Foreign exchange forward contracts Cost of sales (212 ) — — Foreign exchange forward contracts Foreign currency loss, net (5,448 ) — — Cross currency swap contract Foreign currency loss, net — — 4,896 Foreign exchange forward, interest rate, and cross currency swap contracts Interest expense, net — — (1,704 ) Foreign exchange forward contracts Other income, net 546 (189 ) — (6,812 ) (189 ) 3,192 Total amount reclassified $ 48,593 $ (140 ) $ 44,825

Note 22. Segment and Geographic

Note 22. Segment and Geographical Information (Notes)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment and Geographical Information	22. Segment and Geographical Information We operate our business in two segments. Our modules segment involves the design, manufacture, and sale of CdTe solar modules, which convert sunlight into electricity. Third-party customers of our modules segment include integrators and operators of PV solar power systems. Our second segment is our fully integrated systems segment, through which we provide complete turn-key PV solar power systems, or solar solutions, that draw upon our capabilities, which include (i) project development, (ii) EPC services, and (iii) O&M services. We may provide our full EPC services or any combination of individual products and services within our EPC capabilities depending upon the customer and market opportunity. All of our systems segment products and services are for PV solar power systems, which primarily use our solar modules, and we sell such products and services to utilities, independent power producers, commercial and industrial companies, and other system owners. Additionally within our systems segment, we may temporarily own and operate certain of our systems for a period of time based on strategic opportunities or market factors. Our segments are managed by our Chief Executive Officer, who is also considered our chief operating decision maker (“CODM”). Our CODM views sales of solar modules or systems as the primary drivers of our resource allocation, profitability, and cash flows. Our modules segment contributes to our operating results by providing the fundamental technologies and solar modules that drive our business and sales opportunities, and our systems segment contributes to our operating results by using such modules as part of a range of comprehensive PV solar energy solutions, depending on the customer and market opportunity. Our CODM generally makes decisions about allocating resources to our segments and assessing their performance based on gross profit. However, information about segment assets is not reported to the CODM for purposes of making such decisions. Accordingly, we exclude such asset information from our reportable segment financial disclosures. The following tables present certain financial information for our reportable segments for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Year Ended December 31, 2018 Modules Systems Total Net sales $ 502,001 $ 1,742,043 $ 2,244,044 Gross (loss) profit (50,467 ) 442,644 392,177 Depreciation and amortization expense 85,797 18,647 104,444 Goodwill 14,462 — 14,462 Year Ended December 31, 2017 Modules Systems Total Net sales $ 806,398 $ 2,134,926 $ 2,941,324 Gross profit 112,338 436,609 548,947 Depreciation and amortization expense 67,597 24,302 91,899 Goodwill 14,462 — 14,462 Year Ended December 31, 2016 Modules Systems Total Net sales $ 675,452 $ 2,229,111 $ 2,904,563 Gross profit 110,510 527,908 638,418 Depreciation and amortization expense 186,736 17,515 204,251 The following table presents net sales for the years ended December 31, 2018 , 2017 , and 2016 by geographic region, based on the customer country of invoicing (in thousands): 2018 2017 2016 United States $ 1,478,034 $ 2,273,774 $ 2,418,974 Japan 234,814 4,405 5,183 India 232,130 141,491 158,182 Australia 153,163 108,643 9,568 Turkey 19,354 124,433 18,809 Jordan 2,150 2,255 103,022 Spain 741 379 141,319 All other foreign countries 123,658 285,944 49,506 Net sales $ 2,244,044 $ 2,941,324 $ 2,904,563 The following table presents long-lived assets, which include property, plant and equipment, PV solar power systems, and project assets (current and noncurrent) as of December 31, 2018 and 2017 by geographic region, based on the physical location of the assets (in thousands): 2018 2017 Vietnam $ 702,071 $ 252,417 United States 659,854 595,062 Malaysia 532,418 483,884 Japan 319,571 251,559 Chile 240,495 251,208 All other foreign countries 108,871 240,232 Long-lived assets $ 2,563,280 $ 2,074,362

Note 23. Concentrations of Risk

Note 23. Concentrations of Risks (Notes)	12 Months Ended
	Dec. 31, 2018
Risks and Uncertainties [Abstract]
Concentrations of Risks	23. Concentrations of Risks Customer Concentration. The following customers each comprised 10% or more of our total net sales and/or 10% or more of our total accounts receivable for the years ended December 31, 2018 , 2017 , and 2016 : 2018 2017 2016 % of Net Sales % of A/R % of Net Sales % of A/R % of Net Sales % of A/R Customer #1 16 % * * * * * Customer #2 13 % * 47 % * * * Customer #3 * 18 % * * * * Customer #4 * 12 % * * * * Customer #5 * * * 26 % * * Customer #6 * * * 12 % * * Customer #7 * * * * 39 % * Customer #8 * * * * 11 % * Customer #9 * * * * 10 % * Customer #10 * * * * * 32 % Customer #11 * * * * * 12 % —————————— * Net sales and/or accounts receivable for these customers were less than 10% of our total net sales and/or accounts receivable for the period. Geographic Risk. During the year ended December 31, 2018 , our third-party solar module and solar power system net sales were predominantly in the United States. The concentration of our net sales in a limited number of geographic regions exposes us to local economic, public policy, and regulatory risks in such regions. Production. Our products include components that are available from a limited number of suppliers or sources. Shortages of essential components could occur due to increases in demand or interruptions of supply, thereby adversely affecting our ability to meet customer demand for our products. Our solar modules are currently produced at our facilities in Perrysburg, Ohio; Kulim, Malaysia; and Ho Chi Minh City, Vietnam. Damage to or disruption of these facilities could interrupt our business and adversely affect our ability to generate net sales.

Note 2. Summary of Significan_2

Note 2. Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation. These consolidated financial statements include the accounts of First Solar, Inc. and its subsidiaries and are prepared in accordance with U.S. GAAP. We eliminated all intercompany transactions and balances during consolidation. Certain prior year balances were reclassified to conform to the current year presentation.
Use of Estimates	Use of Estimates. The preparation of consolidated financial statements in conformity with U.S. GAAP requires us to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and the accompanying notes. On an ongoing basis, we evaluate our estimates, including those related to inputs used to recognize revenue over time, accrued solar module collection and recycling liabilities, product warranties, accounting for income taxes, long-lived asset impairments, and testing goodwill. Despite our intention to establish accurate estimates and reasonable assumptions, actual results could differ materially from such estimates and assumptions.
Fair Value Measurements	Fair Value Measurements. We measure certain assets and liabilities at fair value, which is defined as the price that would be received from the sale of an asset or paid to transfer a liability (i.e., an exit price) on the measurement date in an orderly transaction between market participants in the principal or most advantageous market for the asset or liability. Our fair value measurements use the following hierarchy, which prioritizes valuation inputs based on the extent to which the inputs are observable in the market. • Level 1 – Valuation techniques in which all significant inputs are unadjusted quoted prices from active markets for assets or liabilities that are identical to the assets or liabilities being measured. • Level 2 – Valuation techniques in which significant inputs include quoted prices from active markets for assets or liabilities that are similar to the assets or liabilities being measured and/or quoted prices for assets or liabilities that are identical or similar to the assets or liabilities being measured from markets that are not active. Also, model-derived valuations in which all significant inputs are observable in active markets are Level 2 valuation techniques. • Level 3 – Valuation techniques in which one or more significant inputs are unobservable. Such inputs reflect our estimate of assumptions that market participants would use to price an asset or liability.
Cash and Cash Equivalents, and Restricted Cash	Cash and Cash Equivalents. We consider highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents with the exception of time deposits, which are presented as marketable securities. Restricted Cash . Restricted cash consists of cash and cash equivalents held by various banks to secure certain of our letters of credit and other such deposits designated for the construction or operation of systems projects as well as the payment of amounts related to project specific debt financings. Restricted cash also includes cash and cash equivalents held in custodial accounts to fund the estimated future costs of our solar module collection and recycling obligations. Restricted cash for our letters of credit is classified as current or noncurrent based on the maturity date of the corresponding letter of credit. Restricted cash for project construction, operation, and financing is classified as current or noncurrent based on the intended use of the restricted funds. Restricted cash held in custodial accounts is classified as noncurrent to align with the nature of the corresponding collection and recycling liabilities.
Marketable Securities and Restricted Investments	Marketable Securities and Restricted Investments. We determine the classification of our marketable securities and restricted investments at the time of purchase and reevaluate such designation at each balance sheet date. As of December 31, 2018 and 2017 , all of our marketable securities and restricted investments were classified as available-for-sale debt securities. Accordingly, we record them at fair value and account for the net unrealized gains and losses as part of “ Accumulated other comprehensive (loss) income ” until realized. We record realized gains and losses on the sale of our marketable securities and restricted investments in “ Other income, net ” computed using the specific identification method. We may sell marketable securities prior to their stated maturities after consideration of our liquidity requirements. We view unrestricted securities with maturities beyond 12 months as available to support our current operations and, accordingly, classify such securities as current assets under “ Marketable securities ” in the consolidated balance sheets. Restricted investments consist of long-term duration marketable securities that we hold in custodial accounts to fund the estimated future costs of our solar module collection and recycling obligations. Accordingly, we classify restricted investments as noncurrent assets under “ Restricted cash and investments ” in the consolidated balance sheets. All of our available-for-sale marketable securities and restricted investments are subject to a periodic impairment review. We consider a marketable security or restricted investment to be impaired when its fair value is less than its cost basis, in which case we would further review the security or investment to determine if it is other-than-temporarily impaired. In performing such an evaluation, we review factors such as the length of time and the extent to which its fair value has been below its cost basis, the financial condition of the issuer and any changes thereto, our intent to sell, and whether it is more likely than not that we will be required to sell the marketable security or restricted investment before we have recovered its cost basis. If a marketable security or restricted investment were other-than-temporarily impaired, we write it down through “ Other income, net ” to its impaired value and establish that value as its new cost basis.
Accounts Receivables Trade and Allowance for Doubtful Accounts	Accounts Receivable Trade and Allowance for Doubtful Accounts . We record trade accounts receivable for our unconditional rights to consideration arising from our performance under contracts with customers. The carrying value of such receivables, net of the allowance for doubtful accounts, represents their estimated net realizable value. We estimate our allowance for doubtful accounts for specific trade receivable balances based on historical collection trends, the age of outstanding trade receivables, existing economic conditions, and the financial security, if any, associated with the receivables. Past-due trade receivable balances are written off when our internal collection efforts have been unsuccessful. Our module and other equipment sales generally include up to 45-day payment terms following the transfer of control of the products to the customer. In addition, certain module and equipment sale agreements may require a down payment for a portion of the transaction price upon or shortly after entering into the agreement or related purchase order. Payment terms for sales of our solar power systems, EPC services, and operations and maintenance services vary by contract but are generally due upon demand or within several months of satisfying the associated performance obligations. As a practical expedient, we do not adjust the promised amount of consideration for the effects of a significant financing component when we expect, at contract inception, that the period between our transfer of a promised product or service to a customer and when the customer pays for that product or service will be one year or less. We typically do not include extended payment terms in our contracts with customers.
Accounts Receivable, Unbilled	Accounts Receivable, Unbilled . Accounts receivable, unbilled represents a contract asset for revenue that has been recognized in advance of billing the customer, which is common for long-term construction contracts. For example, we typically recognize revenue from contracts for the construction and sale of PV solar power systems over time using cost based input methods, which recognize revenue and gross profit as work is performed based on the relationship between actual costs incurred compared to the total estimated costs of the contract. Accordingly, revenue could be recognized in advance of billing the customer, resulting in an amount recorded to “ Accounts receivable, unbilled and retainage .” Once we have an unconditional right to consideration under a construction contract, we typically bill our customer and reclassify the “ Accounts receivable, unbilled and retainage ” to “ Accounts receivable trade, net .” Billing requirements vary by contract but are generally structured around the completion of certain construction milestones. We assess our unbilled accounts receivable for impairment in accordance with the allowance for doubtful accounts policy described above.
Retainage	Retainage. Certain of our EPC contracts for PV solar power systems we build contain retainage provisions. Retainage represents a contract asset for the portion of the contract price earned by us for work performed, but held for payment by the customer as a form of security until we reach certain construction milestones. We consider whether collectibility of such retainage is reasonably assured in connection with our overall assessment of the collectibility of amounts due or that will become due under our EPC contracts. Retainage included within “ Accounts receivable, unbilled and retainage ” is expected to be billed and collected within the next 12 months. After we satisfy the EPC contract requirements and have an unconditional right to consideration, we typically bill for retainage and reclassify such amounts to “ Accounts receivable trade, net .”
Inventories - Current and Noncurrent	Inventories – Current and Noncurrent. We report our inventories at the lower of cost or net realizable value. We determine cost on a first-in, first-out basis and include both the costs of acquisition and the costs of manufacturing in our inventory costs. These costs include direct materials, direct labor, and indirect manufacturing costs, including depreciation and amortization. Our capitalization of costs into inventory is based on the normal utilization of our plants. If our plant utilization is abnormally low, the portion of our indirect manufacturing costs related to the abnormal utilization level is expensed as incurred. Other abnormal manufacturing costs, such as wasted materials or excess yield losses, are also expensed as incurred. Finished goods inventory is comprised exclusively of solar modules that have not yet been installed in a PV solar power plant under construction or sold to a third-party customer. As needed, we may purchase a critical raw material that is used in our core production process in quantities that exceed anticipated consumption within our normal operating cycle (which is 12 months). We classify such raw materials that we do not expect to consume within our normal operating cycle as noncurrent. We regularly review the cost of inventories, including noncurrent inventories, against their estimated net realizable value and record write-downs if any inventories have costs in excess of their net realizable values. We also regularly evaluate the quantities and values of our inventories, including noncurrent inventories, in light of current market conditions and trends, among other factors, and record write-downs for any quantities in excess of demand or for any obsolescence. This evaluation considers the use of modules in our systems business, expected demand, anticipated sales prices, strategic raw material requirements, new product development schedules, product obsolescence, product merchantability, and other factors. Market conditions are subject to change, and actual consumption of our inventory could differ from forecasted demand.
Balance of Systems Parts	Balance of Systems Parts. BoS parts represent mounting, electrical, and other construction parts purchased for PV solar power systems to be constructed or currently under construction, which are not yet installed in a system. These construction parts include items such as posts, tilt brackets, tables, harnesses, combiner boxes, inverters, cables, tracker equipment, and other parts that we may purchase or assemble for the systems we construct. We carry these parts at the lower of cost or net realizable value and determine our BoS costs on a weighted-average basis. BoS parts do not include any solar modules that we manufacture.
Property, Plant and Equipment	Property, Plant and Equipment. We report our property, plant and equipment at cost, less accumulated depreciation. Cost includes the price paid to acquire or construct the assets, required installation costs, interest capitalized during the construction period, and any expenditures that substantially add to the value of or substantially extend the useful life of the assets. We capitalize costs related to computer software obtained or developed for internal use, which generally includes enterprise-level business and finance software that we customize to meet our specific operational requirements. We expense repair and maintenance costs at the time we incur them. We begin depreciation for our property, plant and equipment when they are placed in service. We consider such assets to be placed in service when they are both in the location and condition for their intended use. We compute depreciation expense using the straight-line method over the estimated useful lives of assets, as presented in the table below. We depreciate leasehold improvements over the shorter of their estimated useful lives or the remaining term of the lease. The estimated useful life of an asset is reassessed whenever applicable facts and circumstances indicate a change in the estimated useful life of such asset has occurred. Useful Lives in Years Buildings and building improvements 25 – 40 Manufacturing machinery and equipment 5 – 10 Furniture, fixtures, computer hardware, and computer software 3 – 7 Leasehold improvements up to 15
PV Solar Power Systems	PV Solar Power Systems. PV solar power systems represent project assets that we may temporarily own and operate after being placed in service. We report our PV solar power systems at cost, less accumulated depreciation. When we are entitled to incentive tax credits for our systems, we reduce the related carrying value of the assets by the amount of the tax credits, which reduces future depreciation. We begin depreciation for PV solar power systems when they are placed in service. We compute depreciation expense for the systems using the straight-line method over the shorter of the term of the related PPA or 25 years. Accordingly, our current PV solar power systems have estimated useful lives ranging from 19 to 25 years.
Project Assets	Project Assets. Project assets primarily consist of costs related to solar power projects in various stages of development that are capitalized prior to the completion of the sale of the project, including projects that may have begun commercial operation under PPAs and are actively marketed and intended to be sold. These project related costs include costs for land, development, and construction of a PV solar power system. Development costs may include legal, consulting, permitting, transmission upgrade, interconnection, and other similar costs. We typically classify project assets as noncurrent due to the nature of solar power projects (long-lived assets) and the time required to complete all activities to develop, construct, and sell projects, which is typically longer than 12 months. Once we enter into a definitive sales agreement, we classify such project assets as current until the sale is completed and we have met all of the criteria to recognize the sale as revenue. Any income generated by a project while it remains within project assets is accounted for as a reduction to our basis in the project. If a project is completed and begins commercial operation prior to the closing of a sales arrangement, the completed project will remain in project assets until placed in service. We present all expenditures related to the development and construction of project assets, whether fully or partially owned, as a component of cash flows from operating activities. We review project assets for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. We consider a project commercially viable or recoverable if it is anticipated to be sold for a profit once it is either fully developed or fully constructed. We consider a partially developed or partially constructed project commercially viable or recoverable if the anticipated selling price is higher than the carrying value of the related project assets. We examine a number of factors to determine if the project is expected to be recoverable, including whether there are any changes in environmental, permitting, market pricing, regulatory, or other conditions that may impact the project. Such changes could cause the costs of the project to increase or the selling price of the project to decrease. If a project is not considered recoverable, we impair the respective project assets and adjust the carrying value to the estimated fair value, with the resulting impairment recorded within “Selling, general and administrative” expense.
Interest Capitalization	Interest Capitalization . We capitalize interest as part of the historical cost of acquiring or constructing certain assets, including property, plant and equipment; project assets; and PV solar power systems. Interest capitalized for property, plant and equipment or PV solar power systems is depreciated over the estimated useful life of the related assets when they are placed in service. We charge interest capitalized for project assets to cost of sales when such assets are sold and we have met all revenue recognition criteria. We capitalize interest to the extent that interest cost has been incurred and payments have been made to acquire, construct, or develop an asset. We cease capitalization of interest for assets in development or under construction if the assets are substantially complete or if we have sold such assets.
Asset Impairments	Asset Impairments. We assess long-lived assets classified as “held and used,” including our property, plant and equipment; project assets; PV solar power systems; and intangible assets for impairment whenever events or changes in circumstances arise, including consideration of technological obsolescence, that may indicate that the carrying amount of such assets may not be recoverable. These events and changes in circumstances may include a significant decrease in the market price of a long-lived asset; a significant adverse change in the extent or manner in which a long-lived asset is being used or in its physical condition; a significant adverse change in the business climate that could affect the value of a long-lived asset; an accumulation of costs significantly in excess of the amount originally expected for the acquisition or construction of a long-lived asset; a current-period operating or cash flow loss combined with a history of such losses or a projection of future losses associated with the use of a long-lived asset; or a current expectation that, more likely than not, a long-lived asset will be sold or otherwise disposed of significantly before the end of its previously estimated useful life. For purposes of recognition and measurement of an impairment loss, long-lived assets are grouped with other assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. When impairment indicators are present, we compare undiscounted future cash flows, including the eventual disposition of the asset group at market value, to the asset group’s carrying value to determine if the asset group is recoverable. If the carrying value of the asset group exceeds the undiscounted future cash flows, we measure any impairment by comparing the fair value of the asset group to its carrying value. Fair value is generally determined by considering (i) internally developed discounted cash flows for the asset group, (ii) third-party valuations, and/or (iii) information available regarding the current market value for such assets. If the fair value of an asset group is determined to be less than its carrying value, an impairment in the amount of the difference is recorded in the period that the impairment indicator occurs. Estimating future cash flows requires significant judgment, and such projections may vary from the cash flows eventually realized. We consider a long-lived asset to be abandoned after we have ceased use of such asset and we have no intent to use or repurpose the asset in the future. Abandoned long-lived assets are recorded at their salvage value, if any. We classify long-lived assets we plan to sell, excluding project assets and PV solar power systems, as held for sale on our consolidated balance sheets only after certain criteria have been met including: (i) management has the authority and commits to a plan to sell the asset, (ii) the asset is available for immediate sale in its present condition, (iii) an active program to locate a buyer and the plan to sell the asset have been initiated, (iv) the sale of the asset is probable within 12 months, (v) the asset is being actively marketed at a reasonable sales price relative to its current fair value, and (vi) it is unlikely that the plan to sell will be withdrawn or that significant changes to the plan will be made. We record assets held for sale at the lower of their carrying value or fair value less costs to sell. If, due to unanticipated circumstances, such assets are not sold in the 12 months after being classified as held for sale, then held for sale classification will continue as long as the above criteria are still met.
Ventures and Variable Interest Entities	Ventures and Variable Interest Entities. In the normal course of business, we establish wholly owned project companies which may be considered variable interest entities (“VIEs”). We consolidate wholly owned VIEs when we are considered the primary beneficiary of such entities. Additionally, we have, and may in the future form, joint venture type arrangements, including partnerships and partially owned limited liability companies or similar legal structures, with one or more third parties primarily to develop, construct, own, and/or sell solar power projects. We analyze all of our ventures and classify them into two groups: (i) ventures that must be consolidated because they are either not VIEs and we hold a majority voting interest, or because they are VIEs and we are the primary beneficiary and (ii) ventures that do not need to be consolidated because they are either not VIEs and we hold a minority voting interest, or because they are VIEs and we are not the primary beneficiary. Ventures are considered VIEs if (i) the total equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support; (ii) as a group, the holders of the equity investment at risk lack the ability to make certain decisions, the obligation to absorb expected losses, or the right to receive expected residual returns; or (iii) an equity investor has voting rights that are disproportionate to its economic interest and substantially all of the entity’s activities are conducted on behalf of that investor. Our venture agreements typically require us to fund some form of capital for the development and construction of a project, depending upon the opportunity and the market in which our ventures are located. We are considered the primary beneficiary of and are required to consolidate a VIE if we have the power to direct the activities that most significantly impact the VIE’s economic performance and the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the entity. If we determine that we do not have the power to direct the activities that most significantly impact the entity, then we are not the primary beneficiary of the VIE.
Equity Method Investments	Equity Method Investments. We use the equity method of accounting for our investments when we have the ability to significantly influence, but not control, the operations or financial activities of the investee. As part of this evaluation, we consider our participating and protective rights in the venture as well as its legal form. We record our equity method investments at cost and subsequently adjust their carrying amount each period for our share of the earnings or losses of the investee and other adjustments required by the equity method of accounting. Distributions received from our equity method investments are recorded as reductions in the carrying value of such investments and are classified on the consolidated statements of cash flows pursuant to the cumulative earnings approach. Under this approach, distributions received are considered returns on investment and are classified as cash inflows from operating activities unless our cumulative distributions received, less distributions received in prior periods that were determined to be returns of investment, exceed our cumulative equity in earnings recognized from the investment. When such an excess occurs, the current period distributions up to this excess are considered returns of investment and are classified as cash inflows from investing activities. We monitor equity method investments for impairment and record reductions in their carrying values if the carrying amount of an investment exceeds its fair value. An impairment charge is recorded when such impairment is deemed to be other-than-temporary. To determine whether an impairment is other-than-temporary, we consider our ability and intent to hold the investment until the carrying amount is fully recovered. Circumstances that indicate an other-than-temporary impairment may have occurred include factors such as decreases in quoted market prices or declines in the operations of the investee. The evaluation of an investment for potential impairment requires us to exercise significant judgment and to make certain assumptions. The use of different judgments and assumptions could result in different conclusions. We recorded impairment losses related to our equity method investments of $3.5 million , $2.0 million , and $0.6 million , net of tax, during the years ended December 31, 2018 , 2017 , and 2016 , respectively.
Goodwill	Goodwill. Goodwill represents the excess of the purchase price of acquired businesses over the estimated fair value assigned to the individual assets acquired and liabilities assumed. We do not amortize goodwill, but instead are required to test goodwill for impairment at least annually. We perform impairment tests between the scheduled annual test in the fourth quarter if facts and circumstances indicate that it is more likely than not that the fair value of a reporting unit that has goodwill is less than its carrying value. We may first make a qualitative assessment of whether it is more likely than not that a reporting unit’s fair value is less than its carrying value to determine whether it is necessary to perform a quantitative goodwill impairment test. Such qualitative impairment test considers various factors, including macroeconomic conditions, industry and market considerations, cost factors, the overall financial performance of a reporting unit, and any other relevant events affecting our company or a reporting unit. If we determine through the qualitative assessment that a reporting unit’s fair value is more likely than not greater than its carrying value, the quantitative impairment test is not required. If the qualitative assessment indicates it is more likely than not that a reporting unit’s fair value is less than its carrying value, we perform a quantitative impairment test. We may also elect to proceed directly to the quantitative impairment test without considering qualitative factors. The quantitative impairment test is the comparison of the fair value of a reporting unit with its carrying amount, including goodwill. Our reporting units consist of our modules business and our fully integrated systems business. We define the fair value of a reporting unit as the price that would be received to sell the unit as a whole in an orderly transaction between market participants at the measurement date. We primarily use an income approach to estimate the fair value of our reporting units. Significant judgment is required when estimating the fair value of a reporting unit, including the forecasting of future operating results and the selection of discount and expected future growth rates used to determine projected cash flows. If the estimated fair value of a reporting unit exceeds its carrying value, goodwill is not impaired, and no further analysis is required. Conversely, if the carrying value of a reporting unit exceeds its estimated fair value, we record an impairment loss equal to the excess, not to exceed the total amount of goodwill allocated to the reporting unit.
Intangible Assets	Intangible Assets. Intangible assets primarily include developed technologies or in-process research and development (“IPR&D”) from prior business acquisitions, certain PPAs acquired after the associated PV solar power systems were placed in service, and our internally-generated intangible assets, substantially all of which were patents on technologies related to our products and production processes. We record an asset for patents after the patent has been issued based on the legal, filing, and other costs incurred to secure it. IPR&D is initially capitalized at fair value as an intangible asset with an indefinite life and periodically assessed for impairment. When the IPR&D project is complete, it is reclassified as a definite-lived intangible asset. We amortize intangible assets on a straight-line basis over their estimated useful lives, which generally range from 10 to 20 years.
Deferred Revenue	Deferred Revenue. When we receive consideration, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a sales contract, we record deferred revenue, which represents a contract liability. We recognize deferred revenue as net sales after we have transferred control of the goods or services to the customer and all revenue recognition criteria are met. As a practical expedient, we do not adjust the consideration in a contract for the effects of a significant financing component when we expect, at contract inception, that the period between a customer’s down payment and our transfer of a promised product or service to the customer will be one year or less. Additionally, we do not adjust the consideration in a contract for the effects of a significant financing component when the consideration is received as a form of performance security.
Product Warranties	Product Warranties. We provide a limited PV solar module warranty covering defects in materials and workmanship under normal use and service conditions for approximately 10 years. We also typically warrant that modules installed in accordance with agreed-upon specifications will produce at least 98% of their labeled power output rating during the first year, with the warranty coverage reducing by 0.5% every year thereafter throughout the approximate 25-year limited power output warranty period. In resolving claims under both the limited defect and power output warranties, we typically have the option of either repairing or replacing the covered modules or, under the limited power output warranty, providing additional modules to remedy the power shortfall. Our limited module warranties also include an option for us to remedy claims under such warranties, generally exercisable only after the second year of the warranty period, by making certain cash payments. Under the limited workmanship warranty, the optional cash payment will be equal to the original purchase price of the module, reduced by a degradation factor, and under the limited power output warranty, the cash payment will be equal to the shortfall in power output. Such limited module warranties are standard for module sales and may be transferred from the original purchasers of the solar modules to subsequent purchasers upon resale. As an alternative form of our standard limited module power output warranty, we also offer an aggregated or system-level limited module performance warranty. This system-level limited module performance warranty is designed for utility-scale systems and provides 25 -year system-level energy degradation protection. This warranty represents a practical expedient to address the challenge of identifying, from the potential millions of modules installed in a utility-scale system, individual modules that may be performing below warranty thresholds by focusing on the aggregate energy generated by the system rather than the power output of individual modules. The system-level limited module performance warranty is typically calculated as a percentage of a system’s expected energy production, adjusted for certain actual site conditions, with the warranted level of performance declining each year in a linear fashion, but never falling below 80% during the term of the warranty. In resolving claims under the system-level limited module performance warranty to restore the system to warranted performance levels, we first must validate that the root cause of the issue is due to module performance; we then have the option of either repairing or replacing the covered modules, providing supplemental modules, or making a cash payment. Consistent with our limited module power output warranty, when we elect to satisfy a warranty claim by providing replacement or supplemental modules under the system-level module performance warranty, we do not have any obligation to pay for the labor to remove or install modules. In addition to our limited solar module warranties described above, for PV solar power systems we construct, we typically provide limited warranties for defects in engineering design, installation, and BoS part workmanship for a period of one to two years following the substantial completion of a system or a block within the system. In resolving claims under such BoS warranties, we have the option of remedying the defect through repair or replacement. When we recognize revenue for module or system sales, we accrue liabilities for the estimated future costs of meeting our limited warranty obligations. We make and revise these estimates based primarily on the number of our solar modules under warranty installed at customer locations, our historical experience with warranty claims, our monitoring of field installation sites, our internal testing of and the expected future performance of our solar modules and BoS parts, and our estimated per-module replacement costs.
Accrued Solar Module Collection and Recycling Liability	Accrued Solar Module Collection and Recycling Liability. Historically, we have recognized expense at the time of sale for the estimated cost of our future obligations for collecting and recycling solar modules covered by our solar module collection and recycling program. See Note 13. “Solar Module Collection and Recycling Liability” for further information.
Asset Retirement Obligations	Asset Retirement Obligations. We develop, construct, and operate certain project assets and PV solar power systems with land lease agreements that include a requirement for the removal of the assets at the end of the lease. We also lease certain land for our manufacturing facilities and administrative offices under agreements that require the removal of our property or leasehold improvements upon termination of the lease. We recognize such asset retirement obligations (“AROs”) in the period in which they are incurred based on the present value of estimated third-party decommissioning costs, and we capitalize the associated asset retirement costs as part of the carrying amount of the related assets. Once an asset is placed in service, the asset retirement cost is subsequently depreciated on a straight-line basis over the estimated useful life of the asset. Changes in AROs resulting from the passage of time are recognized as an increase in the carrying amount of the liability and as accretion expense. Our AROs were included within “ Other liabilities ” at December 31, 2018 and 2017 and totaled $18.9 million and $16.7 million , respectively.
Derivative Instruments	Derivative Instruments. We recognize derivative instruments on our consolidated balance sheets at their fair value. On the date that we enter into a derivative contract, we designate the derivative instrument as a fair value hedge, a cash flow hedge, a hedge of a net investment in a foreign operation, or a derivative instrument that will not be accounted for using hedge accounting methods. As of December 31, 2018 and 2017 , all of our derivative instruments were designated either as cash flow hedges or as derivative instruments not accounted for using hedge accounting methods. We record changes in the fair value of a derivative instrument that is highly effective and that is designated and qualifies as a cash flow hedge in “ Accumulated other comprehensive (loss) income ” until our earnings are affected by the variability of the cash flows from the underlying hedge. We record any hedge ineffectiveness and amounts excluded from effectiveness testing in current period earnings within “ Other income, net .” We report changes in the fair value of derivative instruments that are not designated or do not qualify for hedge accounting in current period earnings. We classify cash flows from derivative instruments on the consolidated statements of cash flows in the same category as the item being hedged or on a basis consistent with the nature of the instrument. At the inception of a hedge, we formally document all relationships between hedging instruments and the underlying hedged items as well as our risk-management objective and strategy for undertaking the hedge transaction. We also formally assess (both at inception and on an ongoing basis) whether our derivative instruments are highly effective in offsetting changes in the fair value or cash flows of the underlying hedged items and whether those derivatives are expected to remain highly effective in future periods. When we determine that a derivative instrument is not highly effective as a hedge, we discontinue hedge accounting prospectively. In all situations in which we discontinue hedge accounting and the derivative instrument remains outstanding, we carry the derivative instrument at its fair value on our consolidated balance sheets and recognize subsequent changes in its fair value in current period earnings.
Business Combinations	Business Combinations. We account for business combinations using the acquisition method of accounting and record intangible assets separate from goodwill. Such intangible assets are recorded at fair value based on estimates as of the date of acquisition. Goodwill is recorded as the residual amount of the purchase price consideration less the fair value assigned to the individual assets acquired and liabilities assumed as of the date of acquisition. We charge acquisition related costs that are not part of the purchase price consideration to “ Selling, general and administrative ” as they are incurred. These costs typically include transaction and integration costs, such as legal, accounting, and other professional fees. We account for any contingent consideration, which represents an obligation of the acquirer to transfer additional assets or equity interests to the former owner as part of the exchange if specified future events occur or conditions are met, at fair value either as a liability or as equity depending on the terms of the acquisition agreement.
Revenue Recognition	Revenue Recognition – Module and Other Equipment Sales. We recognize revenue for module and other equipment sales (e.g., module plus arrangements) at a point in time following the transfer of control of such products to the customer, which typically occurs upon shipment or delivery depending on the terms of the underlying contracts. For module and other equipment sales contracts that contain multiple performance obligations, such as the shipment or delivery of solar modules and other BoS parts, we allocate the transaction price to each performance obligation identified in the contract based on relative standalone selling prices, or estimates of such prices, and recognize the related revenue as control of each individual product is transferred to the customer, in satisfaction of the corresponding performance obligations. Revenue Recognition – Solar Power System Sales and/or EPC Services . We generally recognize revenue for sales of solar power systems and/or EPC services over time as our performance creates or enhances an energy generation asset controlled by the customer. Furthermore, the sale of a solar power system when combined with EPC services represents a single performance obligation for the development and construction of a single generation asset. For such sale arrangements, we recognize revenue using cost based input methods, which recognize revenue and gross profit as work is performed based on the relationship between actual costs incurred compared to the total estimated costs of the contract, after consideration of our customers’ commitment to perform its obligations under the contract, which is typically measured through the receipt of cash deposits or other forms of financial security issued by creditworthy financial institutions or parent entities . For sales of solar power systems in which we obtain an interest in the project sold to the customer, we recognize all of the revenue for the consideration received, including the fair value of the noncontrolling interest we obtained, and defer any profit associated with the interest obtained through “ Equity in earnings, net of tax .” We may also recognize revenue for the sale of a solar power system after it has been completed due to the timing of when we enter into the associated sales contract with the customer. In applying cost based input methods of revenue recognition, we use the actual costs incurred relative to the total estimated costs (including solar module costs) to determine our progress towards contract completion and to calculate the corresponding amount of revenue and gross profit to recognize. Cost based input methods of revenue recognition are considered a faithful depiction of our efforts to satisfy long-term construction contracts and therefore reflect the transfer of goods to a customer under such contracts. Costs incurred that do not contribute to satisfying our performance obligations (“inefficient costs”) are excluded from our input methods of revenue recognition as the amounts are not reflective of our transferring control of the system to the customer. Costs incurred towards contract completion may include costs associated with solar modules, direct materials, labor, subcontractors, and other indirect costs related to contract performance. We recognize solar module and direct material costs as incurred when such items have been installed in a system. Cost based input methods of revenue recognition require us to make estimates of net contract revenues and costs to complete our projects. In making such estimates, significant judgment is required to evaluate assumptions related to the amount of net contract revenues, including the impact of any performance incentives, liquidated damages, and other payments to customers. Significant judgment is also required to evaluate assumptions related to the costs to complete our projects, including materials, labor, contingencies, and other system costs. If the estimated total costs on any contract, including any inefficient costs, are greater than the net contract revenues, we recognize the entire estimated loss in the period the loss becomes known. The cumulative effect of revisions to estimates related to net contract revenues or costs to complete contracts are recorded in the period in which the revisions to estimates are identified and the amounts can be reasonably estimated. The effect of the changes on future periods are recognized as if the revised estimates had been used since revenue was initially recognized under the contract. Such revisions could occur in any reporting period, and the effects may be material depending on the size of the contracts or the changes in estimates. As part of our solar power system sales, we conduct performance testing of a system prior to substantial completion to confirm the system meets its operational and capacity expectations noted in the EPC agreement. In addition, we may provide an energy performance test during the first or second year of a system’s operation to demonstrate that the actual energy generation for the applicable period meets or exceeds the modeled energy expectation, after certain adjustments. In certain instances, a bonus payment may be received at the end of the applicable test period if the system performs above a specified level. Conversely, if there is an underperformance event with regards to these tests, we may incur liquidated damages as a percentage of the EPC contract price. Such performance guarantees represent a form of variable consideration and are estimated at contract inception at their most likely amount and updated at the end of each reporting period as additional performance data becomes available and only to the extent that it is probable that a significant reversal of any incremental revenue will not occur. Revenue Recognition – Operations and Maintenance. We recognize revenue for standard, recurring O&M services over time as customers receive and consume the benefits of such services, which typically include 24/7 system monitoring, certain PPA and other agreement compliance, NERC compliance, large generator interconnection agreement compliance, energy forecasting, performance engineering analysis, regular performance reporting, turn-key maintenance services including spare parts and corrective maintenance repair, warranty management, and environmental services. Other ancillary O&M services, such as equipment replacement, weed abatement, landscaping, or solar module cleaning, are recognized as revenue as the services are provided and billed to the customer. Costs of O&M services are expensed in the period in which they are incurred. As part of our O&M service offerings, we typically offer an effective availability guarantee, which stipulates that a system will be available to generate a certain percentage of total possible energy during a specific period after adjusting for factors outside of our control as the service provider. If system availability exceeds a contractual threshold, we may receive a bonus payment, or if system availability falls below a separate threshold, we may incur liquidated damages for certain lost energy under the PPA. Such bonuses or liquidated damages represent a form of variable consideration and are estimated and recognized over time as customers receive and consume the benefits of the O&M services. Revenue Recognition – Energy Generation. We sell energy generated by PV solar power systems under PPAs or on an open contract basis. For energy sold under PPAs, which may qualify as a lease, we recognize revenue each period based on the volume of energy delivered to the customer (i.e., the PPA off-taker) and the price stated in the PPA. For energy sold on an open contract basis, we recognize revenue at the point in time the energy is delivered to the grid based on the prevailing spot market prices.
Shipping and Handling Costs	Shipping and Handling Costs. We account for shipping and handling activities related to contracts with customers as costs to fulfill our promise to transfer the associated products. Accordingly, we record amounts billed for shipping and handling costs as a component of net sales, and classify such costs as a component of cost of sales.
Taxes Collected from Customers and Remitted to Governmental Authorities	Taxes Collected from Customers and Remitted to Governmental Authorities. We exclude from our measurement of transaction prices all taxes assessed by governmental authorities that are both (i) imposed on and concurrent with a specific revenue-producing transaction and (ii) collected from customers. Accordingly, such tax amounts are not included as a component of net sales or cost of sales.
Research and Development Expense	Research and Development Expense. We incur research and development costs during the process of researching and developing new products and enhancing our existing products, technologies, and manufacturing processes. Our research and development costs consist primarily of employee compensation, materials, outside services, and depreciation. We expense these costs as incurred until the resulting product has been completed, tested, and made ready for commercial manufacturing.
Production Start-Up	Production Start-Up. Production start-up expense consists primarily of employee compensation and other costs associated with operating a production line before it has been qualified for full production, including the cost of raw materials for solar modules run through the production line during the qualification phase and applicable facility related costs. Costs related to equipment upgrades and implementation of manufacturing process improvements are also included in production start-up expense as well as costs related to the selection of a new site, related legal and regulatory costs, and costs to maintain our plant replication program to the extent we cannot capitalize these expenditures.
Restructuring and Exit Activities	Restructuring and Exit Activities. We record costs associated with exit activities, such as one-time employee termination benefits, when management approves and commits to a plan of termination or over the future service period, if any. Other costs associated with exit activities may include contract termination costs, including costs related to leased facilities to be abandoned or subleased, and facility and employee relocation costs.
Share-Based Compensation	Share-Based Compensation. We recognize share-based compensation expense for the estimated grant-date fair value of equity awards issued as compensation to employees over the requisite service period, which is generally four years. For awards with performance conditions, we recognize share-based compensation expense if it is probable that the performance conditions will be achieved. We account for forfeitures of share-based awards as such forfeitures occur. Accordingly, when an associate’s employment is terminated, all previously unvested awards granted to such associate are forfeited, which results in a benefit to share-based compensation expense in the period of such associate’s termination equal to the cumulative expense recorded through the termination date for such unvested awards. We recognize share-based compensation expense for awards with graded vesting schedules on a straight-line basis over the requisite service periods for each separately vesting portion of the award as if each award was in substance multiple awards.
Foreign Currency Translation	Foreign Currency Translation. The functional currencies of certain of our foreign subsidiaries are their local currencies. Accordingly, we apply period-end exchange rates to translate their assets and liabilities and daily transaction exchange rates to translate their revenues, expenses, gains, and losses into U.S. dollars. We include the associated translation adjustments as a separate component of “ Accumulated other comprehensive (loss) income ” within stockholders’ equity. The functional currency of our subsidiaries in Canada, Chile, Malaysia, Singapore, and Vietnam is the U.S. dollar; therefore, we do not translate their financial statements. Gains and losses arising from the remeasurement of monetary assets and liabilities denominated in currencies other than a subsidiary’s functional currency are included in “ Foreign currency loss, net ” in the period in which they occur.
Income Taxes	Income Taxes. We use the asset and liability method to account for income taxes whereby we calculate deferred tax assets or liabilities using the enacted tax rates and tax law applicable to when any temporary differences are expected to reverse. We establish valuation allowances, when necessary, to reduce deferred tax assets to the extent it is more likely than not that such deferred tax assets will not be realized. We do not provide deferred taxes related to the U.S. GAAP basis in excess of the outside tax basis in the investment in our foreign subsidiaries to the extent such amounts relate to indefinitely reinvested earnings and profits of such foreign subsidiaries. Income tax expense includes (i) deferred tax expense, which generally represents the net change in deferred tax assets or liabilities during the year plus any change in valuation allowances, and (ii) current tax expense, which represents the amount of tax currently payable to or receivable from taxing authorities. We only recognize tax benefits related to uncertain tax positions that are more likely than not of being sustained upon examination. For those positions that satisfy such recognition criteria, the amount of tax benefit that we recognize is the largest amount of tax benefit that is more likely than not of being sustained on ultimate settlement of the uncertain tax position.
Per Share Data	Per Share Data. Basic net income or loss per share is computed by dividing net income or loss by the weighted-average number of common shares outstanding for the period. Diluted net income per share is computed giving effect to all potentially dilutive common shares, including restricted and performance stock units and stock purchase plan shares, unless there is a net loss for the period. In computing diluted net income per share, we utilize the treasury stock method.
Accumulated Other Comprehensive Income or Loss	Accumulated Other Comprehensive Income or Loss. Our accumulated other comprehensive income or loss includes foreign currency translation adjustments, unrealized gains and losses on available-for-sale debt securities, and unrealized gains and losses on derivative instruments designated and qualifying as cash flow hedges. We record these components of accumulated other comprehensive income or loss net of tax and release such tax effects when the underlying components affect earnings.

Note 2. Summary of Significan_3

Note 2. Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Schedule of Property, Plant and Equipment, Useful Lives [Table Text Block]	Useful Lives in Years Buildings and building improvements 25 – 40 Manufacturing machinery and equipment 5 – 10 Furniture, fixtures, computer hardware, and computer software 3 – 7 Leasehold improvements up to 15

Note 6. Goodwill and Intangib_2

Note 6. Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The changes in the carrying amount of goodwill, by reporting unit, for the years ended December 31, 2018 and 2017 were as follows (in thousands): Balance at December 31, 2017 Acquisitions (Impairments) Balance at December 31, 2018 Modules $ 407,827 $ — $ 407,827 Accumulated impairment losses (393,365 ) — (393,365 ) Total $ 14,462 $ — $ 14,462 Balance at December 31, 2016 Acquisitions (Impairments) Balance at December 31, 2017 Modules $ 407,827 $ — $ 407,827 Accumulated impairment losses (393,365 ) — (393,365 ) Total $ 14,462 $ — $ 14,462
Schedule of Intangible Assets, Net	The following tables summarize our intangible assets at December 31, 2018 and 2017 (in thousands): December 31, 2018 Gross Amount Accumulated Amortization Net Amount Developed technology $ 97,714 $ (33,093 ) $ 64,621 Power purchase agreements 6,486 (648 ) 5,838 Patents 7,408 (3,705 ) 3,703 Total $ 111,608 $ (37,446 ) $ 74,162 December 31, 2017 Gross Amount Accumulated Amortization Net Amount Developed technology $ 76,959 $ (24,140 ) $ 52,819 Power purchase agreements 6,486 (324 ) 6,162 Patents 7,068 (3,077 ) 3,991 In-process research and development (1) 17,255 — 17,255 Total $ 107,768 $ (27,541 ) $ 80,227
Schedule of Intangible Asset Future Amortization Expense	Estimated future amortization expense for our definite-lived intangible assets was as follows at December 31, 2018 (in thousands): Amortization Expense 2019 $ 10,436 2020 10,786 2021 10,784 2022 10,759 2023 10,474 Thereafter 20,923 Total amortization expense $ 74,162

Note 7. Cash, Cash Equivalent_2

Note 7. Cash, Cash Equivalents, and Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2018
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Schedule of Cash, Cash Equivalents, and Marketable Securities	Cash, cash equivalents, and marketable securities consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Cash and cash equivalents: Cash $ 1,202,774 $ 2,142,949 Money market funds 200,788 125,585 Total cash and cash equivalents 1,403,562 2,268,534 Marketable securities: Foreign debt 318,646 238,858 Foreign government obligations 98,621 152,850 U.S. debt 44,468 73,671 Time deposits 681,969 255,000 Total marketable securities 1,143,704 720,379 Total cash, cash equivalents, and marketable securities $ 2,547,266 $ 2,988,913
Reconciliation of Cash, Cash Equivalents, and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within our consolidated balance sheets as of December 31, 2018 and 2017 to the total of such amounts as presented in the consolidated statements of cash flows (in thousands): Balance Sheet Line Item 2018 2017 Cash and cash equivalents Cash and cash equivalents $ 1,403,562 $ 2,268,534 Restricted cash – current (1) Prepaid expenses and other current assets 19,671 11,120 Restricted cash – noncurrent (1) Restricted cash and investments 139,390 50,822 Total cash, cash equivalents, and restricted cash $ 1,562,623 $ 2,330,476 —————————— (1) See Note 8. “Restricted Cash and Investments” to our consolidated financial statements for discussion of our “Restricted cash” arrangements.
Available-for-sale Marketable Securities	The following tables summarize the unrealized gains and losses related to our available-for-sale marketable securities, by major security type, as of December 31, 2018 and 2017 (in thousands): As of December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign debt $ 320,056 $ 468 $ 1,878 $ 318,646 Foreign government obligations 99,189 — 568 98,621 U.S. debt 44,625 53 210 44,468 Time deposits 681,969 — — 681,969 Total $ 1,145,839 $ 521 $ 2,656 $ 1,143,704 As of December 31, 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign debt $ 240,643 $ 3 $ 1,788 $ 238,858 Foreign government obligations 153,999 — 1,149 152,850 U.S. debt 73,746 — 75 73,671 Time deposits 255,000 — — 255,000 Total $ 723,388 $ 3 $ 3,012 $ 720,379
Available-for-sale Marketable Securities Continuous Unrealized Loss Position	The following tables show unrealized losses and fair values for those marketable securities that were in an unrealized loss position as of December 31, 2018 and 2017 , aggregated by major security type and the length of time the marketable securities have been in a continuous loss position (in thousands): As of December 31, 2018 In Loss Position for Less Than 12 Months In Loss Position for 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Foreign debt $ 150,842 $ 802 $ 94,446 $ 1,076 $ 245,288 $ 1,878 Foreign government obligations — — 98,621 568 98,621 568 U.S. debt 15,356 32 14,085 178 29,441 210 Total $ 166,198 $ 834 $ 207,152 $ 1,822 $ 373,350 $ 2,656 As of December 31, 2017 In Loss Position for Less Than 12 Months In Loss Position for 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Foreign debt $ 119,869 $ 735 $ 88,919 $ 1,053 $ 208,788 $ 1,788 Foreign government obligations 31,467 289 121,383 860 152,850 1,149 U.S. debt $ 73,671 $ 75 $ — $ — $ 73,671 $ 75 Total $ 225,007 $ 1,099 $ 210,302 $ 1,913 $ 435,309 $ 3,012
Available-for-sale Marketable Securities by Maturity	The contractual maturities of our marketable securities as of December 31, 2018 were as follows (in thousands): Fair Value One year or less $ 904,384 One year to two years 161,961 Two years to three years 77,359 Total $ 1,143,704

Note 8. Restricted Cash and I_2

Note 8. Restricted Cash and Investments (Tables)	12 Months Ended
	Dec. 31, 2018
Restricted Cash and Investments [Abstract]
Restricted Cash And Investments	Restricted cash and investments consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Restricted cash $ 139,390 $ 50,822 Restricted investments 179,000 373,961 Total restricted cash and investments (1) $ 318,390 $ 424,783 —————————— (1) There was an additional $19.7 million and $11.1 million of restricted cash included within “ Prepaid expenses and other current assets ” at December 31, 2018 and 2017 , respectively.
Restricted Available For Sale Securities	The following tables summarize the unrealized gains and losses related to our restricted investments, by major security type, as of December 31, 2018 and 2017 (in thousands): As of December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign government obligations $ 73,798 $ 14,234 $ 235 $ 87,797 U.S. government obligations 97,223 416 6,436 91,203 Total $ 171,021 $ 14,650 $ 6,671 $ 179,000 As of December 31, 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Foreign government obligations $ 127,436 $ 62,483 $ — $ 189,919 U.S. government obligations 174,624 12,944 3,526 184,042 Total $ 302,060 $ 75,427 $ 3,526 $ 373,961
Schedule of Unrealized Loss on Restricted Investments	The following tables show unrealized losses and fair values for those restricted investments that were in an unrealized loss position as of December 31, 2018 and 2017 , aggregated by major security type and the length of time the restricted investments have been in a continuous loss position (in thousands): As of December 31, 2018 In Loss Position for In Loss Position for Total Fair Unrealized Fair Unrealized Fair Unrealized Foreign government obligations $ 41,335 $ 235 $ — $ — $ 41,335 $ 235 U.S. government obligations — — 87,401 6,436 87,401 6,436 Total $ 41,335 $ 235 $ 87,401 $ 6,436 $ 128,736 $ 6,671 As of December 31, 2017 In Loss Position for In Loss Position for Total Fair Unrealized Fair Unrealized Fair Unrealized U.S. government obligations $ — $ — $ 107,731 $ 3,526 $ 107,731 $ 3,526 Total $ — $ — $ 107,731 $ 3,526 $ 107,731 $ 3,526

Note 9. Consolidated Balance _2

Note 9. Consolidated Balance Sheet Details (Tables)	12 Months Ended
	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Schedule of Accounts Receivable	Accounts receivable trade, net consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Accounts receivable trade, gross $ 129,644 $ 213,776 Allowance for doubtful accounts (1,362 ) (1,979 ) Accounts receivable trade, net $ 128,282 $ 211,797 At December 31, 2018 and 2017 , $8.5 million and $16.8 million , respectively, of our accounts receivable trade, net were secured by letters of credit, bank guarantees, or other forms of financial security issued by creditworthy financial institutions. Accounts receivable, unbilled and retainage Accounts receivable, unbilled and retainage consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Accounts receivable, unbilled $ 441,666 $ 172,594 Retainage 16,500 2,014 Accounts receivable, unbilled and retainage $ 458,166 $ 174,608
Schedule of Inventory, Current and Noncurrent	Inventories consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Raw materials $ 224,329 $ 148,968 Work in process 41,294 14,085 Finished goods 252,372 122,594 Inventories $ 517,995 $ 285,647 Inventories – current $ 387,912 $ 172,370 Inventories – noncurrent $ 130,083 $ 113,277
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Prepaid expenses $ 90,981 $ 41,447 Prepaid income taxes 59,319 31,944 Indirect tax receivables 26,327 26,553 Restricted cash 19,671 11,120 Derivative instruments 2,364 4,303 Other current assets 44,399 42,535 Prepaid expenses and other current assets $ 243,061 $ 157,902
Schedule of Property, Plant and Equipment, Net	Property, plant and equipment, net consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Land $ 14,382 $ 8,181 Buildings and improvements 567,605 424,266 Machinery and equipment 1,826,434 1,059,103 Office equipment and furniture 178,011 157,512 Leasehold improvements 49,055 48,951 Construction in progress 405,581 641,263 Property, plant and equipment, gross 3,041,068 2,339,276 Accumulated depreciation (1,284,857 ) (1,184,739 ) Property, plant and equipment, net $ 1,756,211 $ 1,154,537
Schedule of PV Solar Power Systems, Net	PV solar power systems, net consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 PV solar power systems, gross $ 343,061 $ 451,045 Accumulated depreciation (34,421 ) (33,937 ) PV solar power systems, net $ 308,640 $ 417,108
Schedule of Capitalized Interest	The cost of constructing project assets includes interest costs incurred during the construction period. The components of interest expense and capitalized interest were as follows during the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Interest cost incurred $ (31,752 ) $ (27,457 ) $ (26,157 ) Interest cost capitalized – property, plant and equipment — — 1,878 Interest cost capitalized – project assets 5,831 1,692 3,741 Interest expense, net $ (25,921 ) $ (25,765 ) $ (20,538 )
Schedule of Project Assets	Project assets consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Project assets – development costs, including project acquisition and land costs $ 298,070 $ 250,590 Project assets – construction costs 200,359 252,127 Project assets 498,429 502,717 Project assets – current $ 37,930 $ 77,931 Project assets – noncurrent $ 460,499 $ 424,786
Schedule of Other Assets, Noncurrent	Other assets consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Deferred rent $ 27,249 $ 26,760 Indirect tax receivables 22,487 15,253 Notes receivable (1) 8,017 10,495 Income taxes receivable 4,444 4,454 Other 33,495 28,570 Other assets $ 95,692 $ 85,532 —————————— (1) In April 2009 , we entered into a credit facility agreement with a solar power project entity of one of our customers for an available amount of €17.5 million to provide financing for a PV solar power system. The credit facility bears interest at 8.0% per annum, payable quarterly, with the full amount due in December 2026. As of December 31, 2018 and 2017 , the balance outstanding on the credit facility was €7.0 million ( $8.0 million and $8.4 million , respectively).
Schedule of Accrued Expenses	Accrued expenses consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Accrued project costs $ 147,162 $ 55,834 Accrued property, plant and equipment 89,905 133,433 Accrued inventory 53,075 24,830 Accrued compensation and benefits 41,937 73,985 Product warranty liability (1) 27,657 28,767 Other 81,844 49,978 Accrued expenses $ 441,580 $ 366,827 —————————— (1) See Note 15. “Commitments and Contingencies” to our consolidated financial statements for discussion of our “Product warranty liability.”
Schedule of Other Current Liabilities	Other current liabilities consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Derivative instruments $ 7,294 $ 27,297 Contingent consideration (1) 665 6,162 Financing liability (2) — 5,161 Indemnification liabilities (1) — 2,876 Other 6,421 7,261 Other current liabilities $ 14,380 $ 48,757 —————————— (1) See Note 15. “Commitments and Contingencies” to our consolidated financial statements for discussion of our “Contingent consideration” and “Indemnification liabilities” arrangements. (2) See Note 12. “Equity Method Investments” to our consolidated financial statements for discussion of the financing liabilities associated with our leaseback of the Maryland Solar project.
Schedule of Other Liabilities	Other liabilities consisted of the following at December 31, 2018 and 2017 (in thousands): 2018 2017 Product warranty liability (1) $ 193,035 $ 195,507 Other taxes payable 83,058 89,724 Transition tax liability (2) 77,016 93,233 Deferred revenue 48,014 63,257 Derivative instruments 9,205 5,932 Contingent consideration (1) 2,250 3,153 Commercial letter of credit liability (1) — 43,396 Financing liability (3) — 29,822 Other 55,261 44,430 Other liabilities $ 467,839 $ 568,454 —————————— (1) See Note 15. “Commitments and Contingencies” to our consolidated financial statements for discussion of our “Product warranty liability,” “Contingent consideration,” and “Commercial letter of credit liability” arrangements. (2) See Note 19. “Income Taxes” to our consolidated financial statements for discussion of the one-time transition tax on accumulated earnings of foreign subsidiaries as a result of the Tax Act. (3) See Note 12. “Equity Method Investments” to our consolidated financial statements for discussion of the financing liabilities associated with our leaseback of the Maryland Solar project.

Note 10. Derivative Financial_2

Note 10. Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]	The following tables present the fair values of derivative instruments included in our consolidated balance sheets as of December 31, 2018 and 2017 (in thousands): December 31, 2018 Prepaid Expenses and Other Current Assets Other Current Liabilities Other Liabilities Derivatives designated as hedging instruments: Foreign exchange forward contracts $ 158 $ — $ — Total derivatives designated as hedging instruments $ 158 $ — $ — Derivatives not designated as hedging instruments: Foreign exchange forward contracts $ 2,206 $ 7,096 $ — Interest rate swap contracts — 198 9,205 Total derivatives not designated as hedging instruments $ 2,206 $ 7,294 $ 9,205 Total derivative instruments $ 2,364 $ 7,294 $ 9,205 December 31, 2017 Prepaid Expenses and Other Current Assets Other Current Liabilities Other Liabilities Derivatives designated as hedging instruments: Foreign exchange forward contracts $ 252 $ 13,240 $ — Total derivatives designated as hedging instruments $ 252 $ 13,240 $ — Derivatives not designated as hedging instruments: Foreign exchange forward contracts $ 4,051 $ 14,057 $ — Interest rate swap contracts — — 5,932 Total derivatives not designated as hedging instruments $ 4,051 $ 14,057 $ 5,932 Total derivative instruments $ 4,303 $ 27,297 $ 5,932
Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]	The following table presents the pretax amounts related to derivative instruments designated as cash flow hedges affecting accumulated other comprehensive income or loss and our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Foreign Exchange Forward Contracts Interest Rate Swap Contract Cross Currency Swap Contract Total Balance in accumulated other comprehensive (loss) income at December 31, 2015 $ 162 $ (16 ) $ (2,017 ) $ (1,871 ) Amounts recognized in other comprehensive (loss) income 2,513 (2 ) 5,108 7,619 Amounts reclassified to earnings impacting: Foreign currency loss, net — — (4,896 ) (4,896 ) Interest expense, net (119 ) 18 1,805 1,704 Balance in accumulated other comprehensive (loss) income at December 31, 2016 2,556 — — 2,556 Amounts recognized in other comprehensive (loss) income (4,468 ) — — (4,468 ) Amounts reclassified to earnings impacting: Other income, net 189 — — 189 Balance in accumulated other comprehensive (loss) income at December 31, 2017 (1,723 ) — — (1,723 ) Amounts recognized in other comprehensive (loss) income (3,760 ) — — (3,760 ) Amounts reclassified to earnings impacting: Net sales 1,698 — — 1,698 Cost of sales 212 — — 212 Foreign currency loss, net 5,448 — — 5,448 Other income, net (546 ) — — (546 ) Balance in accumulated other comprehensive (loss) income at December 31, 2018 $ 1,329 $ — $ — $ 1,329
Derivative Instruments, Gain (Loss) [Table Text Block]	The following table presents gains and losses related to derivative instruments not designated as hedges affecting our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Amount of Gain (Loss) Recognized in Income Income Statement Line Item 2018 2017 2016 Foreign exchange forward contracts Foreign currency loss, net $ 12,113 $ (33,882 ) $ (14,002 ) Interest rate swap contracts Interest expense, net (8,643 ) (5,932 ) —
Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]	As of December 31, 2018 and 2017 , the notional values associated with our foreign exchange forward contracts qualifying as cash flow hedges were as follows (notional amounts and U.S. dollar equivalents in millions): December 31, 2018 Currency Notional Amount USD Equivalent Australian dollar AUD 8.8 $6.2 December 31, 2017 Currency Notional Amount USD Equivalent Indian rupee INR 4,730.0 $74.1 Euro €15.7 $18.8
Schedule of Notional Value of Foreign Exchange Forward Derivatives [Table Text Block]	As of December 31, 2018 and 2017 , the notional values of our foreign exchange forward contracts that do not qualify for hedge accounting were as follows (notional amounts and U.S. dollar equivalents in millions): December 31, 2018 Transaction Currency Notional Amount USD Equivalent Purchase Australian dollar AUD 2.1 $1.5 Sell Australian dollar AUD 52.9 $37.3 Purchase Brazilian real BRL 8.5 $2.2 Sell Canadian dollar CAD 2.9 $2.1 Sell Chilean peso CLP 3,506.6 $5.1 Purchase Euro €115.2 $131.9 Sell Euro €191.8 $219.7 Sell Indian rupee INR 789.2 $11.3 Purchase Japanese yen ¥931.6 $8.4 Sell Japanese yen ¥23,858.8 $216.2 Purchase Malaysian ringgit MYR 34.3 $8.3 Sell Malaysian ringgit MYR 53.8 $12.9 Sell Mexican peso MXN 37.3 $1.9 Purchase Singapore dollar SGD 3.8 $2.8 December 31, 2017 Transaction Currency Notional Amount USD Equivalent Purchase Australian dollar AUD 12.7 $9.9 Sell Australian dollar AUD 56.8 $44.4 Sell Canadian dollar CAD 1.7 $1.4 Sell Chilean peso CLP 10,180.9 $16.6 Purchase Chinese yuan CNY 13.8 $2.1 Purchase Euro €151.4 $181.6 Sell Euro €193.2 $231.7 Purchase Indian rupee INR 645.7 $10.1 Sell Indian rupee INR 8,376.0 $131.1 Sell Japanese yen ¥23,922.2 $212.6 Purchase Malaysian ringgit MYR 31.0 $7.7 Sell Malaysian ringgit MYR 336.5 $83.1 Sell Singapore dollar SGD 3.1 $2.3 Purchase South African rand ZAR 12.5 $1.0 Sell South African rand ZAR 61.1 $5.0

Note 11. Fair Value Measureme_2

Note 11. Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair value assets and liabilities measured on recurring basis	At December 31, 2018 and 2017 , the fair value measurements of our assets and liabilities measured on a recurring basis were as follows (in thousands): Fair Value Measurements at Reporting Date Using December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Cash equivalents: Money market funds $ 200,788 $ 200,788 $ — $ — Marketable securities: Foreign debt 318,646 — 318,646 — Foreign government obligations 98,621 — 98,621 — U.S. debt 44,468 — 44,468 — Time deposits 681,969 681,969 — — Restricted investments 179,000 — 179,000 — Derivative assets 2,364 — 2,364 — Total assets $ 1,525,856 $ 882,757 $ 643,099 $ — Liabilities: Derivative liabilities $ 16,499 $ — $ 16,499 $ — Fair Value Measurements at Reporting Date Using December 31, 2017 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Cash equivalents: Money market funds $ 125,585 $ 125,585 $ — $ — Marketable securities: Foreign debt 238,858 — 238,858 — Foreign government obligations 152,850 — 152,850 — U.S. debt 73,671 — 73,671 — Time deposits 255,000 255,000 — — Restricted investments 373,961 — 373,961 — Derivative assets 4,303 — 4,303 — Total assets $ 1,224,228 $ 380,585 $ 843,643 $ — Liabilities: Derivative liabilities $ 33,229 $ — $ 33,229 $ —
Fair value of financial instruments not measured on a recurring basis	At December 31, 2018 and 2017 , the carrying values and fair values of our financial instruments not measured at fair value were as follows (in thousands): December 31, 2018 December 31, 2017 Carrying Value Fair Value Carrying Value Fair Value Assets: Notes receivable – noncurrent $ 8,017 $ 8,010 $ 10,495 $ 10,516 Notes receivable, affiliate – current — — 20,411 23,317 Notes receivable, affiliates – noncurrent 22,832 24,295 48,370 47,441 Liabilities: Long-term debt, including current maturities (1) $ 479,157 $ 470,124 $ 406,388 $ 416,486 —————————— (1) Excludes capital lease obligations and unamortized discounts and issuance costs.

Note 12. Equity Method Invest_2

Note 12. Equity Method Investments (Tables)	12 Months Ended
	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Equity Method Investments [Table Text Block]	The following table summarizes our equity method investments as of December 31, 2018 and 2017 (in thousands): 2018 2017 8point3 Operating Company, LLC $ — $ 199,477 Clean Energy Collective, LLC — 6,521 Other 3,186 11,232 Equity method investments $ 3,186 $ 217,230
Equity Method Investments, Summarized Financial Information [Table Text Block]	The following table presents summarized financial information, in the aggregate, for our significant equity method investees, as provided to us by the investees (in thousands): Fiscal 2018 Fiscal 2017 Fiscal 2016 Summary statement of operations information: Net sales $ 28,736 $ 70,089 $ 125,643 Operating (loss) income (38,606 ) 24,661 55,266 Net (loss) income (1) (39,280 ) 46,713 63,893 Net (loss) income attributable to equity method investees (1) (2) (45,228 ) 53,183 190,240 As of Fiscal 2018 As of Fiscal 2017 Summary balance sheet information: Current assets $ — $ 36,744 Long-term assets — 1,573,115 Current liabilities — 7,648 Long-term liabilities — 706,885 Noncontrolling interests, including redeemable noncontrolling interests — 72,945 —————————— (1) The difference between Net (loss) income and Net (loss) income attributable to equity method investees is due to OpCo’s tax equity financing facilities with third-party investors that hold noncontrolling ownership interests in certain of its subsidiaries. Accordingly, earnings or losses are allocated to such tax equity investors using the Hypothetical Liquidation at Book Value (or “HLBV”) method. During the fiscal 2018, 2017, and 2016 periods, OpCo allocated certain losses to such third-party investors under the HLBV method, which represented the difference between Net (loss) income and Net (loss) income attributable to equity method investees. (2) Our proportionate share of OpCo’s net loss for fiscal 2018 excluded the investee’s impairment loss related to the Maryland Solar project as we accounted for the sale-leaseback of the project as a financing transaction and the associated financing liability exceeded the carrying value of the project.

Note 14. Debt (Tables)

Note 14. Debt (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Instruments [Abstract]
Schedule of Long-term Debt Instruments	Our long-term debt consisted of the following at December 31, 2018 and 2017 (in thousands): Balance (USD) Loan Agreement Currency 2018 2017 Revolving Credit Facility USD $ — $ — Luz del Norte Credit Facilities USD 188,849 185,675 Ishikawa Credit Agreement JPY 157,834 121,446 Japan Credit Facility JPY — 10,710 Tochigi Credit Facility JPY 25,468 — Mashiko Credit Agreement JPY — — Royal Solar Credit Facility JPY — — Marikal Credit Facility INR — 7,384 Hindupur Credit Facility INR — 18,722 Anantapur Credit Facility INR 16,101 — Tungabhadra Credit Facility INR 13,934 — Manildra Credit Facility AUD — 62,451 Beryl Credit Facility AUD 76,971 — Capital lease obligations Various — 156 Long-term debt principal 479,157 406,544 Less: unamortized discounts and issuance costs (12,366 ) (13,004 ) Total long-term debt 466,791 393,540 Less: current portion (5,570 ) (13,075 ) Noncurrent portion $ 461,221 $ 380,465
Schedule of Borrowing Rate on Debt	Our long-term debt borrowing rates as of December 31, 2018 were as follows: Loan Agreement December 31, 2018 Revolving Credit Facility 4.50% Luz del Norte Credit Facilities (1) Fixed rate loans at bank rate plus 3.50% Variable rate loans at 91-Day U.S. Treasury Bill Yield or LIBOR plus 3.50% Ishikawa Credit Agreement Senior loan facility at 6-month TIBOR plus 0.75% (2) Consumption tax facility at 3-month TIBOR plus 0.5% Japan Credit Facility 1-month TIBOR plus 0.5% Tochigi Credit Facility 3-month TIBOR plus 1.0% Anantapur Credit Facility INR overnight indexed swap rate plus 1.5% Tungabhadra Credit Facility INR overnight indexed swap rate plus 1.5% Beryl Credit Facility Construction loan facility at 1-month BBSY plus 1.75% (2) GST facility at 1-month BBSY plus 1.00% —————————— (1) Outstanding balance comprised of $161.1 million of fixed rate loans and $27.7 million of variable rate loans as of December 31, 2018 . (2) We have entered into interest rate swap contracts to hedge portions of these variable rates. See Note 10. “Derivative Financial Instruments” to our consolidated financial statements for additional information.
Schedule of Maturities of Long-term Debt	At December 31, 2018 , the future principal payments on our long-term debt were due as follows (in thousands): Total Debt 2019 $ 5,673 2020 26,935 2021 66,014 2022 12,221 2023 71,620 Thereafter 296,694 Total long-term debt future principal payments $ 479,157

Note 15. Commitments and Cont_2

Note 15. Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Non Cancelable Leases Future Minimum Payments	Future minimum payments under our operating leases were as follows as of December 31, 2018 (in thousands): Total Minimum Lease Payments 2019 $ 13,839 2020 9,031 2021 8,309 2022 7,824 2023 7,749 Thereafter 100,062 Total operating lease obligations $ 146,814
Schedule of Product Warranty Liability	Product warranty activities during the years ended December 31, 2018 , 2017 , and 2016 were as follows (in thousands): 2018 2017 2016 Product warranty liability, beginning of period $ 224,274 $ 252,408 $ 231,751 Accruals for new warranties issued 14,132 23,313 35,256 Settlements (11,851 ) (11,329 ) (16,266 ) Changes in estimate of product warranty liability (5,863 ) (40,118 ) 1,667 Product warranty liability, end of period $ 220,692 $ 224,274 $ 252,408 Current portion of warranty liability $ 27,657 $ 28,767 $ 40,079 Noncurrent portion of warranty liability $ 193,035 $ 195,507 $ 212,329

Note 16. Revenue from Contrac_2

Note 16. Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Disaggregation Revenue, by Type of Revenue [Table Text Block]	The following table represents a disaggregation of revenue from contracts with customers for the years ended December 31, 2018 , 2017 , and 2016 along with the reportable segment for each category (in thousands): Category Segment 2018 2017 2016 Solar modules Modules $ 502,001 $ 806,398 $ 675,453 Solar power systems Systems 1,244,175 1,927,122 1,131,961 EPC services Systems 347,560 45,525 892,814 O&M services Systems 103,186 101,024 93,476 Module plus Systems — 3,236 84,926 Energy generation (1) Systems 47,122 58,019 25,933 Net sales $ 2,244,044 $ 2,941,324 $ 2,904,563 —————————— (1) During the years ended December 31, 2017 and 2016 , the majority of energy generated and sold by our PV solar power systems was accounted for under ASC 840 consistent with the classification of the associated PPAs.
Changes in Estimates Systems Business [Table Text Block]	The following table outlines the impact on revenue of net changes in estimated transaction prices and input costs for systems related sales contracts (both increases and decreases) for the years ended December 31, 2018 , 2017 , and 2016 as well as the number of projects that comprise such changes. For purposes of the table, we only include projects with changes in estimates that have a net impact on revenue of at least $1.0 million during the periods presented with the exception of the sales and use tax matter described below, for which the aggregate change in estimate has been presented. Also included in the table is the net change in estimate as a percentage of the aggregate revenue for such projects. 2018 2017 2016 Number of projects (1) 24 5 12 Increase (decrease) in revenue from net changes in transaction prices (in thousands) (1) $ 63,361 $ 3,579 $ (67,292 ) Increase in revenue from net changes in input cost estimates (in thousands) 1,548 5,047 164,920 Net increase in revenue from net changes in estimates (in thousands) $ 64,909 $ 8,626 $ 97,628 Net change in estimate as a percentage of aggregate revenue 0.6 % 0.6 % 1.6 %
Changes in Contract Assets and Liabilities [Table Text Block]	The following table reflects the changes in our contract assets, which we classify as “Accounts receivable, unbilled” or “Retainage,” and our contract liabilities, which we classify as “Deferred revenue,” for the year ended December 31, 2018 (in thousands): 2018 2017 Change Accounts receivable, unbilled $ 441,666 $ 172,594 Retainage 16,500 2,014 Accounts receivable, unbilled and retainage $ 458,166 $ 174,608 $ 283,558 162 % Deferred revenue (1) $ 177,769 $ 145,073 $ 32,696 23 % —————————— (1) Includes $48.0 million and $63.3 million of long-term deferred revenue classified as “ Other liabilities ” on our consolidated balance sheets as of December 31, 2018 and 2017 , respectively.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]	The following table represents our remaining performance obligations as of December 31, 2018 for sales of solar power systems, including uncompleted sold projects, projects under sales contracts subject to conditions precedent, and EPC agreements for partner developed projects that we are constructing or expect to construct. Such table excludes remaining performance obligations for any sales arrangements that had not fully satisfied the criteria to be considered a contract with a customer pursuant to the requirements of ASC 606. We expect to recognize $0.7 billion of revenue for such contracts through the later of the substantial completion or the closing dates of the projects. Project/Location Project Size in MW AC Revenue Category EPC Contract/Partner Developed Project Expected Year Revenue Recognition Will Be Completed % of Revenue Recognized Phoebe, Texas 250 EPC Innergix Renewable Energy 2019 12% GA Solar 4, Georgia (1) 200 Solar power systems Origis Energy USA 2020 11% Rosamond, California 150 Solar power systems Clearway Energy Group 2019 57% Willow Springs, California 100 Solar power systems D.E. Shaw Renewable Investments 2019 96% Grange Hall, Florida 61 EPC Tampa Electric Company 2019 98% Peace Creek, Florida 55 EPC Tampa Electric Company 2019 70% Troy Solar, Indiana 51 EPC Southern Indiana Gas and Electric Company 2020 —% Lake Hancock, Florida 50 EPC Tampa Electric Company 2019 34% Total 917

Note 18. Share-Based Compensa_2

Note 18. Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs	The following table presents share-based compensation expense recognized in our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Cost of sales $ 6,422 $ 6,809 $ 7,598 Selling, general and administrative 21,646 22,165 17,830 Research and development 5,714 5,740 3,284 Production start-up 372 407 — Total share-based compensation expense $ 34,154 $ 35,121 $ 28,712 The following table presents share-based compensation expense by type of award for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Restricted and performance stock units $ 32,223 $ 32,309 $ 25,076 Unrestricted stock 1,637 1,757 1,677 Stock purchase plan — 394 1,332 33,860 34,460 28,085 Net amount released from inventory 294 661 627 Total share-based compensation expense $ 34,154 $ 35,121 $ 28,712
Schedule of Nonvested Restricted Stock Units Activity	The following is a summary of our restricted stock unit activity, including performance stock unit activity, for the year ended December 31, 2018 : Number of Shares Weighted-Average Grant-Date Fair Value Unvested restricted stock units at December 31, 2017 2,302,906 $ 38.55 Restricted stock units granted (1) 739,855 67.44 Restricted stock units vested (490,682) 44.46 Restricted stock units forfeited (77,792) 51.04 Unvested restricted stock units at December 31, 2018 2,474,287 $ 45.63 —————————— (1) Restricted stock units granted include the maximum amount of performance stock units available for issuance under our long-term incentive program for key executive officers and associates. The actual number of shares to be issued will depend on the relative attainment of the performance metrics described above.

Note 19. Income Taxes (Tables)

Note 19. Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]	The U.S. and non-U.S. components of our income or loss before income taxes for the years ended December 31, 2018 , 2017 , and 2016 were as follows (in thousands): 2018 2017 2016 U.S. income $ (49,353 ) $ (22,868 ) $ (426,791 ) Non-U.S. income 162,500 224,983 (110,460 ) Income (loss) before taxes and equity in earnings $ 113,147 $ 202,115 $ (537,251 )
Schedule of Components of Income Tax [Table Text Block]	The components of our income tax expense or benefit for the years ended December 31, 2018 , 2017 , and 2016 were as follows (in thousands): 2018 2017 2016 Current (benefit) expense: Federal $ (44,267 ) $ 116,956 $ (14,389 ) State (13,568 ) 3,009 1,303 Foreign 8,788 11,099 (29,009 ) Total current (benefit) expense (49,047 ) 131,064 (42,095 ) Deferred expense: Federal 31,530 226,570 90,319 State 2,387 5,335 (9,536 ) Foreign 18,571 9,027 (15,521 ) Total deferred expense 52,488 240,932 65,262 Total income tax expense $ 3,441 $ 371,996 $ 23,167
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	Our income tax results differed from the amount computed by applying the relevant U.S. statutory federal corporate income tax rate to our income or loss before income taxes for the following reasons for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Tax Percent Tax Percent Tax Percent Statutory income tax expense (benefit) $ 23,761 21.0 % $ 70,740 35.0 % $ (188,038 ) 35.0 % Provisional effect of Tax Act — — % 408,090 201.9 % — — % Changes in valuation allowance 19,064 16.8 % 9,534 4.7 % 2,412 (0.4 )% Foreign tax rate differential 14,117 12.5 % (22,048 ) (10.9 )% 6,833 (1.3 )% State tax, net of federal benefit (7,580 ) (6.7 )% 4,397 2.2 % (8,655 ) 1.6 % Non-deductible expenses 4,636 4.1 % 2,703 1.3 % 324 — % Share-based compensation (2,105 ) (1.9 )% 1,161 0.6 % (23,283 ) 4.3 % Change in tax contingency (6,273 ) (5.5 )% 959 0.5 % (34,541 ) 6.4 % Foreign dividend income 16,570 14.6 % 540 0.3 % 248,013 (46.2 )% Goodwill — — % — — % 22,468 (4.2 )% Tax credits (8,431 ) (7.5 )% (18,445 ) (9.1 )% (15,435 ) 2.9 % Return to provision adjustments (25,307 ) (22.3 )% (35,191 ) (17.4 )% 11,757 (2.2 )% Effect of tax holiday (26,277 ) (23.2 )% (46,643 ) (23.1 )% 4,640 (0.9 )% Other 1,266 1.1 % (3,801 ) (1.9 )% (3,328 ) 0.7 % Reported income tax expense $ 3,441 3.0 % $ 371,996 184.1 % $ 23,167 (4.3 )%
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	The items that gave rise to our deferred taxes as of December 31, 2018 and 2017 were as follows (in thousands): 2018 2017 Deferred tax assets: Net operating losses $ 108,149 $ 124,281 Accrued expenses 55,754 62,345 Property, plant and equipment 18,796 35,104 Compensation 18,564 9,442 Goodwill 9,223 12,140 Long-term contracts 4,967 4,554 Inventory 4,079 7,601 Capitalized interest 2,948 — Equity in earnings 2,693 — Deferred expenses 2,165 2,057 Other 17,373 12,584 Deferred tax assets, gross 244,711 270,108 Valuation allowance (159,546 ) (143,818 ) Deferred tax assets, net of valuation allowance 85,165 126,290 Deferred tax liabilities: Restricted investments and derivatives (7,586 ) (10,680 ) Acquisition accounting / basis difference (5,420 ) (5,880 ) Investments in foreign subsidiaries (4,425 ) (9,555 ) Equity in earnings — (40,339 ) Capitalized interest — (1,722 ) Other (3,093 ) (7,541 ) Deferred tax liabilities (20,524 ) (75,717 ) Net deferred tax assets and liabilities $ 64,641 $ 50,573
Summary of Valuation Allowance [Table Text Block]	Changes in the valuation allowance against our deferred tax assets were as follows during the years ended December 31, 2018 , 2017 , and 2016 (in thousands): 2018 2017 2016 Valuation allowance, beginning of year $ 143,818 $ 123,936 $ 121,524 Additions 29,359 27,591 13,933 Reversals (13,631 ) (7,709 ) (11,521 ) Valuation allowance, end of year $ 159,546 $ 143,818 $ 123,936
Summary of Income Tax Contingencies [Table Text Block]	A reconciliation of the beginning and ending amount of liabilities associated with uncertain tax positions for the years ended December 31, 2018 , 2017 , and 2016 is as follows (in thousands): 2018 2017 2016 Unrecognized tax benefits, beginning of year $ 84,173 $ 89,256 $ 141,755 Increases related to prior year tax positions — 3,827 — Decreases related to prior year tax positions (2,979 ) — (6,119 ) Decreases from lapse in statute of limitations (10,704 ) (11,840 ) (14,421 ) Decreases relating to settlements with authorities — (2,494 ) (35,416 ) Increases related to current tax positions 1,703 5,424 3,457 Unrecognized tax benefits, end of year $ 72,193 $ 84,173 $ 89,256
Summary of Income Tax Examinations [Table Text Block]	The following table summarizes the tax years that are either currently under audit or remain open and subject to examination by the tax authorities in the most significant jurisdictions in which we operate: Tax Years Australia 2013 - 2017 India 2013 - 2018 Malaysia 2013 - 2017 United States 2008 - 2009; 2013 - 2017

Note 20. Net Income (Loss) Pe_2

Note 20. Net Income (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The calculation of basic and diluted net income (loss) per share for the years ended December 31, 2018 , 2017 , and 2016 was as follows (in thousands, except per share amounts): 2018 2017 2016 Basic net income (loss) per share Numerator: Net income (loss) $ 144,326 $ (165,615 ) $ (416,112 ) Denominator: Weighted-average common shares outstanding 104,745 104,328 102,866 Diluted net income (loss) per share Denominator: Weighted-average common shares outstanding 104,745 104,328 102,866 Effect of restricted and performance stock units and stock purchase plan shares 1,368 — — Weighted-average shares used in computing diluted net income (loss) per share 106,113 104,328 102,866 Net income (loss) per share: Basic $ 1.38 $ (1.59 ) $ (4.05 ) Diluted $ 1.36 $ (1.59 ) $ (4.05 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	The following table summarizes the potential shares of common stock that were excluded from the computation of diluted net income per share for the years ended December 31, 2018 , 2017 , and 2016 as such shares would have had an anti-dilutive effect (in thousands): 2018 2017 2016 Anti-dilutive shares 299 1,021 753

Note 21. Accumulated Other Co_2

Note 21. Accumulated Other Comprehensive (Loss) Income (Tables)	12 Months Ended
	Dec. 31, 2018
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive (Loss) Income	The following table presents the changes in accumulated other comprehensive (loss) income, net of tax, for the year ended December 31, 2018 (in thousands): Foreign Currency Translation Adjustment Unrealized Gain (Loss) on Marketable Securities and Restricted Investments Unrealized Gain (Loss) on Derivative Instruments Total Balance as of December 31, 2017 $ (65,346 ) $ 68,388 $ (783 ) $ 2,259 Other comprehensive loss before reclassifications (1,034 ) (6,077 ) (3,760 ) (10,871 ) Amounts reclassified from accumulated other comprehensive (loss) income — (55,405 ) 6,812 (48,593 ) Net tax effect — 3,735 (996 ) 2,739 Net other comprehensive (loss) income (1,034 ) (57,747 ) 2,056 (56,725 ) Balance as of December 31, 2018 $ (66,380 ) $ 10,641 $ 1,273 $ (54,466 )
Reclassification out of Accumulated Other Comprehensive (Loss) Income	The following table presents the pretax amounts reclassified from accumulated other comprehensive (loss) income into our consolidated statements of operations for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Comprehensive Income Components Income Statement Line Item Amounts Reclassified for the Year Ended December 31, 2018 2017 2016 Unrealized gain on marketable securities and restricted investments Other income, net $ 55,405 $ 49 $ 41,633 Unrealized (loss) gain on derivative contracts: Foreign exchange forward contracts Net sales (1,698 ) — — Foreign exchange forward contracts Cost of sales (212 ) — — Foreign exchange forward contracts Foreign currency loss, net (5,448 ) — — Cross currency swap contract Foreign currency loss, net — — 4,896 Foreign exchange forward, interest rate, and cross currency swap contracts Interest expense, net — — (1,704 ) Foreign exchange forward contracts Other income, net 546 (189 ) — (6,812 ) (189 ) 3,192 Total amount reclassified $ 48,593 $ (140 ) $ 44,825

Note 22. Segment and Geograph_2

Note 22. Segment and Geographical Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The following tables present certain financial information for our reportable segments for the years ended December 31, 2018 , 2017 , and 2016 (in thousands): Year Ended December 31, 2018 Modules Systems Total Net sales $ 502,001 $ 1,742,043 $ 2,244,044 Gross (loss) profit (50,467 ) 442,644 392,177 Depreciation and amortization expense 85,797 18,647 104,444 Goodwill 14,462 — 14,462 Year Ended December 31, 2017 Modules Systems Total Net sales $ 806,398 $ 2,134,926 $ 2,941,324 Gross profit 112,338 436,609 548,947 Depreciation and amortization expense 67,597 24,302 91,899 Goodwill 14,462 — 14,462 Year Ended December 31, 2016 Modules Systems Total Net sales $ 675,452 $ 2,229,111 $ 2,904,563 Gross profit 110,510 527,908 638,418 Depreciation and amortization expense 186,736 17,515 204,251
Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area	The following table presents net sales for the years ended December 31, 2018 , 2017 , and 2016 by geographic region, based on the customer country of invoicing (in thousands): 2018 2017 2016 United States $ 1,478,034 $ 2,273,774 $ 2,418,974 Japan 234,814 4,405 5,183 India 232,130 141,491 158,182 Australia 153,163 108,643 9,568 Turkey 19,354 124,433 18,809 Jordan 2,150 2,255 103,022 Spain 741 379 141,319 All other foreign countries 123,658 285,944 49,506 Net sales $ 2,244,044 $ 2,941,324 $ 2,904,563
Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country	The following table presents long-lived assets, which include property, plant and equipment, PV solar power systems, and project assets (current and noncurrent) as of December 31, 2018 and 2017 by geographic region, based on the physical location of the assets (in thousands): 2018 2017 Vietnam $ 702,071 $ 252,417 United States 659,854 595,062 Malaysia 532,418 483,884 Japan 319,571 251,559 Chile 240,495 251,208 All other foreign countries 108,871 240,232 Long-lived assets $ 2,563,280 $ 2,074,362

Note 23. Concentrations of Ri_2

Note 23. Concentrations of Risks (Tables)	12 Months Ended
	Dec. 31, 2018
Risks and Uncertainties [Abstract]
Schedules of Concentration of Risk, by Risk Factor	The following customers each comprised 10% or more of our total net sales and/or 10% or more of our total accounts receivable for the years ended December 31, 2018 , 2017 , and 2016 : 2018 2017 2016 % of Net Sales % of A/R % of Net Sales % of A/R % of Net Sales % of A/R Customer #1 16 % * * * * * Customer #2 13 % * 47 % * * * Customer #3 * 18 % * * * * Customer #4 * 12 % * * * * Customer #5 * * * 26 % * * Customer #6 * * * 12 % * * Customer #7 * * * * 39 % * Customer #8 * * * * 11 % * Customer #9 * * * * 10 % * Customer #10 * * * * * 32 % Customer #11 * * * * * 12 % —————————— * Net sales and/or accounts receivable for these customers were less than 10% of our total net sales and/or accounts receivable for the period.

Note 2. Summary of Significan_4

Note 2. Summary of Significant Accounting Policies (Details) - PP&E Table	12 Months Ended
	Dec. 31, 2018
Minimum [Member] | Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	25 years
Minimum [Member] | Manufacturing Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Minimum [Member] | Furniture, Fixtures, Computer Hardware, and Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Maximum [Member] | Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Maximum [Member] | Manufacturing Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Maximum [Member] | Furniture, Fixtures, Computer Hardware, and Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	7 years
Maximum [Member] | Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	15 years

Note 2. Summary of Significan_5

Note 2. Summary of Significant Accounting Policies (Details) - Textuals - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Line Items]
Equity Method Investment, Other than Temporary Impairment	$ 3.5	$ 2	$ 0.6
Standard Limited Module Workmanship Warranty Term	10 years
Standard Limited Module Power Output Warranty, Annual Degradation Percentage	0.50%
Product minimum service life	25 years
Asset Retirement Obligation	$ 18.9	$ 16.7
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Minimum [Member]
Accounting Policies [Line Items]
PV Solar Power Systems, Current Useful Life	19 years
Finite-Lived Intangible Asset, Useful Life	10 years
Standard Limited Module Power Output Warranty	80.00%
Standard Limited EPC Warranty Term	1 year
Maximum [Member]
Accounting Policies [Line Items]
PV Solar Power Systems, Policy Useful Life	25 years
PV Solar Power Systems, Current Useful Life	25 years
Finite-Lived Intangible Asset, Useful Life	20 years
Standard Limited Module Power Output Warranty	98.00%
Standard Limited EPC Warranty Term	2 years

Note 4. Restructuring and Ass_2

Note 4. Restructuring and Asset Impairments (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		$ 0	$ 37,181	$ 743,862
Cadmium Telluride Module Manufacturing and Corporate Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			41,800
Crystalline Silicon Module Manufacturing Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges				81,400
Manufacturing Equipment Impairments [Member] | Cadmium Telluride Module Manufacturing and Corporate Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			27,600	640,300
Manufacturing Equipment Impairments [Member] | Crystalline Silicon Module Manufacturing Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges				35,900
Intangible Assets Impairments [Member] | Crystalline Silicon Module Manufacturing Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges				35,800
Employee Severance [Member] | Cadmium Telluride Module Manufacturing and Corporate Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			7,600	14,100
Employee Severance [Member] | Crystalline Silicon Module Manufacturing Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges				1,300
Other Restructuring [Member] | Cadmium Telluride Module Manufacturing and Corporate Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			$ 6,700	8,100
Other Restructuring [Member] | Crystalline Silicon Module Manufacturing Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges				$ 8,400
Other Restructuring [Member] | Prior Manufacturing Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ (4,700)

Note 5. Business Acquisitions_2

Note 5. Business Acquisitions (Details) - USD ($) $ in Thousands	1 Months Ended
	Oct. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill		$ 14,462	$ 14,462	$ 14,462
Enki Technology [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	100.00%
Payments to Acquire Businesses, Net of Cash Acquired	$ 10,300
Cash Acquired from Acquisition	300
Business combination, contingent consideration liability, noncurrent	7,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent	4,400
Goodwill	4,400
Enki Technology [Member] | In-process research and development [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets	$ 17,300

Note 6. Goodwill and Intangib_3

Note 6. Goodwill and Intangible Assets (Details) - Goodwill - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Accumulated impairment losses			$ (393,365)	$ (393,365)
Goodwill		$ 14,462	14,462	14,462
Goodwill impairment		0	0	(74,930)
Goodwill, period increase (decrease)		0	0
Modules segment [Member]
Goodwill [Line Items]
Goodwill, gross		407,827	407,827	407,827
Accumulated impairment losses		(393,365)	(393,365)
Goodwill		14,462	14,462
Goodwill from acquisition		0	0
Crystalline Silicon Modules Segment [Member]
Goodwill [Line Items]
Goodwill impairment	$ (6,100)
Systems segment [Member]
Goodwill [Line Items]
Goodwill		$ 0	$ 0
Goodwill impairment				$ (68,800)
Measurement Input, Tax Rate [Member] | Minimum [Member]
Goodwill [Line Items]
Goodwill, Measurement Input				10.00%
Measurement Input, Tax Rate [Member] | Maximum [Member]
Goodwill [Line Items]
Goodwill, Measurement Input				35.00%
Measurement Input, Discount Rate [Member] | Minimum [Member]
Goodwill [Line Items]
Goodwill, Measurement Input				11.50%
Measurement Input, Discount Rate [Member] | Maximum [Member]
Goodwill [Line Items]
Goodwill, Measurement Input				18.00%

Note 6. Goodwill and Intangib_4

Note 6. Goodwill and Intangible Assets (Details) - Other Intangible Assets - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Intangible Assets, Net [Abstract]
Intangible assets, gross	$ 111,608	$ 107,768
Intangible assets, accumulated amortization	(37,446)	(27,541)
Intangible assets, net	74,162	80,227
Amortization of intangible assets	9,900	8,300	$ 10,100
Other Intangible Assets, Future Amortization Expense, Current and Five Succeeding Fiscal Years [Abstract]
Other Intangible Assets, Amortization Expense, Next Twelve Months	10,436
Other Intangible Assets, Amortization Expense, Year Two	10,786
Other Intangible Assets, Amortization Expense, Year Three	10,784
Other Intangible Assets, Amortization Expense, Year Four	10,759
Other Intangible Assets, Amortization Expense, Year Five	10,474
Other Intangible Assets, Amortization Expense, Thereafter	20,923
Finite-Lived Intangible Assets, Net	74,162
Developed technology [Member]
Other Intangible Assets, Net [Abstract]
Intangible assets, gross	97,714	76,959
Intangible assets, accumulated amortization	(33,093)	(24,140)
Intangible assets, net	64,621	52,819
Power purchase agreements [Member]
Other Intangible Assets, Net [Abstract]
Intangible assets, gross	6,486	6,486
Intangible assets, accumulated amortization	(648)	(324)
Intangible assets, net	5,838	6,162
Patents [Member]
Other Intangible Assets, Net [Abstract]
Intangible assets, gross	7,408	7,068
Intangible assets, accumulated amortization	(3,705)	(3,077)
Intangible assets, net	3,703	3,991
In-process research and development [Member]
Other Intangible Assets, Net [Abstract]
Intangible assets, gross		17,255
Intangible assets, accumulated amortization		0
Intangible assets, net		$ 17,255
Enki Technology [Member] | Developed technology [Member]
Other Intangible Assets, Net [Abstract]
Intangible assets, gross	$ 17,255
Finite-Lived Intangible Asset, Useful Life	10 years

Note 7. Cash, Cash Equivalent_3

Note 7. Cash, Cash Equivalents, and Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Cash and cash equivalents	$ 1,403,562	$ 2,268,534
Marketable securities	1,143,704	720,379
Total cash, cash equivalents, marketable securities	2,547,266	2,988,913
Restricted cash - current	19,671	11,120
Restricted cash - noncurrent	139,390	50,822
Cash, cash equivalents, restricted cash	1,562,623	2,330,476	$ 1,415,690	$ 1,207,116
Marketable securities, Sale Proceeds	10,800	118,300	159,200
Marketable securities, realized gain			$ 300
Maximum [Member]
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Marketable securities, realized gain	100	100
Foreign debt [Member]
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Marketable securities	318,646	238,858
Foreign government obligations [Member]
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Marketable securities	98,621	152,850
U.S debt [Member]
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Marketable securities	44,468	73,671
Time deposits [Member]
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Marketable securities	681,969	255,000
Cash [Member]
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Cash and cash equivalents	1,202,774	2,142,949
Money Market Funds [Member]
Cash, Cash Equivalents, and Marketable Securities [Line Items]
Cash and cash equivalents	$ 200,788	$ 125,585

Note 7. Cash, Cash Equivalent_4

Note 7. Cash, Cash Equivalents, and Marketable Securities (Details) - Available For Sale $ in Thousands	Dec. 31, 2018USD ($)Investments	Dec. 31, 2017USD ($)Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 1,145,839	$ 723,388
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	521	3
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,656	3,012
Marketable securities	$ 1,143,704	$ 720,379
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Investments	15	16
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 166,198	$ 225,007
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, less than 12 months, accumulated loss	834	1,099
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 months or longer	207,152	210,302
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1,822	1,913
Debt Securities, Available-for-sale, in loss position	373,350	435,309
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	2,656	3,012
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value	904,384
Debt securities, Available-for-sale, Debt Maturities, Rolling Year One Through Two	161,961
Debt securities, Available-for-sale, Debt Maturities, Rolling Year Two Through Three	77,359
Total marketable securities	1,143,704	720,379
Foreign debt [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	320,056	240,643
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	468	3
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1,878	1,788
Marketable securities	318,646	238,858
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	150,842	119,869
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, less than 12 months, accumulated loss	802	735
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 months or longer	94,446	88,919
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1,076	1,053
Debt Securities, Available-for-sale, in loss position	245,288	208,788
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	1,878	1,788
Total marketable securities	318,646	238,858
Foreign government obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	99,189	153,999
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	568	1,149
Marketable securities	98,621	152,850
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	31,467
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, less than 12 months, accumulated loss	0	289
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 months or longer	98,621	121,383
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	568	860
Debt Securities, Available-for-sale, in loss position	98,621	152,850
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	568	1,149
Total marketable securities	98,621	152,850
U.S debt [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	44,625	73,746
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	53	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	210	75
Marketable securities	44,468	73,671
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	15,356	73,671
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, less than 12 months, accumulated loss	32	75
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 months or longer	14,085	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	178	0
Debt Securities, Available-for-sale, in loss position	29,441	73,671
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	210	75
Total marketable securities	44,468	73,671
Time deposits [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	681,969	255,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Marketable securities	681,969	255,000
Debt securities, Available-for-sale, continuous unrealized loss position:
Total marketable securities	$ 681,969	$ 255,000

Note 8. Restricted Cash and I_3

Note 8. Restricted Cash and Investments (Details) - Restricted Cash and Restricted Investments - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2016	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Restricted cash - noncurrent	$ 139,390		$ 50,822
Restricted investments	179,000		373,961
Restricted cash and investments, noncurrent	318,390		424,783
Restricted cash - current	$ 19,671		11,120
Product minimum service life	25 years
Restricted Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Restricted investments	$ 179,000		$ 373,961
Proceeds from sale of restricted investments	231,100	$ 118,200
Realized gain from sale of restricted investments	55,400	$ 41,300
Proceeds from sale of restricted investments withdrawn from custodial accounts	$ 143,100

Note 8. Restricted Cash and I_4

Note 8. Restricted Cash and Investments (Details) - Available For Sale $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)Investments	Dec. 31, 2017USD ($)Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 1,145,839	$ 723,388
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	521	3
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2,656	3,012
Restricted investments	$ 179,000	$ 373,961
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Investments	15	16
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 166,198	$ 225,007
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	834	1,099
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	207,152	210,302
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1,822	1,913
Debt Securities, Available-for-sale, in loss position	373,350	435,309
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	2,656	3,012
Foreign government obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	99,189	153,999
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	568	1,149
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	31,467
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	289
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	98,621	121,383
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	568	860
Debt Securities, Available-for-sale, in loss position	98,621	152,850
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	568	1,149
Restricted Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	171,021	302,060
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	14,650	75,427
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	6,671	3,526
Restricted investments	$ 179,000	$ 373,961
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | Investments	6	6
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 41,335	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	235	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	87,401	107,731
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	6,436	3,526
Debt Securities, Available-for-sale, in loss position	128,736	107,731
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	$ 6,671	3,526
Restricted Investments [Member] | Minimum [Member]
Debt securities, Available-for-sale, continuous unrealized loss position:
Contractual maturities of available-for-sale marketable securities, range start (in years)	11 years
Restricted Investments [Member] | Maximum [Member]
Debt securities, Available-for-sale, continuous unrealized loss position:
Contractual maturities of available-for-sale marketable securities, range end (in years)	18 years
Restricted Investments [Member] | Foreign government obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 73,798	127,436
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	14,234	62,483
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	235	0
Restricted investments	87,797	189,919
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	41,335
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	235
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Available-for-sale, in loss position	41,335
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	235
Restricted Investments [Member] | U.S. government obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	97,223	174,624
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	416	12,944
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	6,436	3,526
Restricted investments	91,203	184,042
Debt securities, Available-for-sale, continuous unrealized loss position:
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	87,401	107,731
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	6,436	3,526
Debt Securities, Available-for-sale, in loss position	87,401	107,731
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, accumulated loss	$ 6,436	$ 3,526

Note 9. Consolidated Balance _3

Note 9. Consolidated Balance Sheet Details (Details) $ in Thousands, € in Millions	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2018EUR (€)	Dec. 31, 2017EUR (€)	Apr. 30, 2009EUR (€)
Accounts receivable trade, net:
Accounts receivable trade, gross	$ 129,644	$ 213,776
Allowance for doubtful accounts	(1,362)	(1,979)
Accounts receivable trade, net	128,282	211,797
Secured accounts receivable	8,500	16,800
Accounts receivable, unbilled	441,666	172,594
Retainage	16,500	2,014
Accounts receivable, unbilled and retainage	458,166	174,608
Inventories:
Raw materials	224,329	148,968
Work in process	41,294	14,085
Finished goods	252,372	122,594
Inventories	517,995	285,647
Inventories - current	387,912	172,370
Inventories - noncurrent	130,083	113,277
Prepaid expenses and other current assets:
Prepaid expenses	90,981	41,447
Prepaid income taxes	59,319	31,944
Indirect tax receivables	26,327	26,553
Restricted cash	19,671	11,120
Derivative instruments	2,364	4,303
Other current assets	44,399	42,535
Prepaid expenses and other current assets	243,061	157,902
Property, plant and equipment, net:
Property, plant and equipment, gross	3,041,068	2,339,276
Accumulated depreciation	(1,284,857)	(1,184,739)
Property, plant and equipment, net	1,756,211	1,154,537
PV solar power systems, net
PV solar power systems, gross	343,061	451,045
Accumulated depreciation	(34,421)	(33,937)
PV solar power systems, net	308,640	417,108
Interest Costs Incurred
Interest cost incurred	(31,752)	(27,457)	$ (26,157)
Interest expense, net	(25,921)	(25,765)	(20,538)
Project Assets - Current and Noncurrent:
Project assets - development costs, including project acquisition and land costs	298,070	250,590
Project assets - construction costs	200,359	252,127
Total project assets	498,429	502,717
Project assets - current	37,930	77,931
Project assets - noncurrent	460,499	424,786
Other Assets, Noncurrent
Deferred rent	27,249	26,760
Indirect Tax Receivables, Noncurrent	22,487	15,253
Notes receivable	8,017	10,495
Income taxes receivable	4,444	4,454
Other	33,495	28,570
Other assets	95,692	85,532
Accrued Expenses
Accrued project costs	147,162	55,834
Accrued property, plant, and equipment	89,905	133,433
Accrued inventory	53,075	24,830
Accrued compensation and benefits	41,937	73,985
Product warranty liability	27,657	28,767
Other	81,844	49,978
Accrued expenses	441,580	366,827
Other current liabilities
Derivative instruments	7,294	27,297
Contingent consideration	665	6,162
Financing liability	0	5,161
Indemnification liabilities	0	2,876
Other	6,421	7,261
Other current liabilities	14,380	48,757
Other liabilities:
Product warranty liability	193,035	195,507
Other taxes payable	83,058	89,724
Transition tax liability, noncurrent	77,016	93,233
Deferred revenue, noncurrent	48,014	63,257
Derivative instruments	9,205	5,932
Contingent consideration	2,250	3,153
Commercial letter of credit liability	0	43,396
Financing liability	0	29,822
Other	55,261	44,430
Other liabilities	467,839	568,454
Credit Facility Agreement [Member]
Other Assets, Noncurrent
Notes receivable	8,000	8,400		€ 7	€ 7
Notes Receivable Initial Available Amount | €						€ 17.5
Note Receivable Interest Rate						8.00%
Property, plant and equipment [Member]
Depreciation
Depreciation	109,100	91,400	211,200
Interest Costs Incurred
Interest costs, capitalized during period	0	0	1,878
PV solar power systems [Member]
Depreciation
Depreciation	15,300	19,800	11,700
Project assets
Interest Costs Incurred
Interest costs, capitalized during period	5,831	1,692	$ 3,741
Land [Member]
Property, plant and equipment, net:
Property, plant and equipment, gross	14,382	8,181
Building and improvements [Member]
Property, plant and equipment, net:
Property, plant and equipment, gross	567,605	424,266
Machinery and equipment [Member]
Property, plant and equipment, net:
Property, plant and equipment, gross	1,826,434	1,059,103
Office equipment and furniture [Member]
Property, plant and equipment, net:
Property, plant and equipment, gross	178,011	157,512
Leasehold improvements [Member]
Property, plant and equipment, net:
Property, plant and equipment, gross	49,055	48,951
Construction in progress [Member]
Property, plant and equipment, net:
Property, plant and equipment, gross	$ 405,581	$ 641,263

Note 10. Derivative Financial_3

Note 10. Derivative Financial Instruments (Details) - Summary - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	$ 2,364	$ 4,303
Prepaid Expenses and Other Current Assets [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	158	252
Prepaid Expenses and Other Current Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,206	4,051
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(7,294)	(27,297)
Other Current Liabilities [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	13,240
Other Current Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	7,294	14,057
Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(9,205)	(5,932)
Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Other Noncurrent Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	9,205	5,932
Foreign exchange forward contracts [Member] | Prepaid Expenses and Other Current Assets [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	158	252
Foreign exchange forward contracts [Member] | Prepaid Expenses and Other Current Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,206	4,051
Foreign exchange forward contracts [Member] | Other Current Liabilities [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	13,240
Foreign exchange forward contracts [Member] | Other Current Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	7,096	14,057
Foreign exchange forward contracts [Member] | Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Foreign exchange forward contracts [Member] | Other Noncurrent Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Interest rate swap contract [Member] | Prepaid Expenses and Other Current Assets [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Interest rate swap contract [Member] | Other Current Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	198	0
Interest rate swap contract [Member] | Other Noncurrent Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 9,205	$ 5,932

Note 10. Derivative Financial_4

Note 10. Derivative Financial Instruments (Details) - Hedging Relationship - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Balance in accumulated other comprehensive (loss) income	$ 1,329	$ (1,723)	$ 2,556	$ (1,871)
Amounts recognized in other comprehensive (loss) income	(3,760)	(4,468)	7,619
Net sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	1,698
Cost of sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	212
Foreign currency loss, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	5,448		(4,896)
Other income (expense), net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	(546)	189
Interest expense, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net			1,704
Not Designated as Hedging Instrument [Member] | Foreign exchange forward contracts [Member] | Foreign currency loss, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	12,113	(33,882)	(14,002)
Not Designated as Hedging Instrument [Member] | Interest rate swap contract [Member] | Interest expense, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(8,643)	(5,932)	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign exchange forward contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Balance in accumulated other comprehensive (loss) income	1,329	(1,723)	2,556	162
Amounts recognized in other comprehensive (loss) income	(3,760)	(4,468)	2,513
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign exchange forward contracts [Member] | Net sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	1,698
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign exchange forward contracts [Member] | Cost of sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	212
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign exchange forward contracts [Member] | Foreign currency loss, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	5,448		0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign exchange forward contracts [Member] | Other income (expense), net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	(546)	189
Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net	0	0	0
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	500	700	(900)
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign exchange forward contracts [Member] | Interest expense, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net			(119)
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest rate swap contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Balance in accumulated other comprehensive (loss) income	0	0	0	(16)
Amounts recognized in other comprehensive (loss) income	0	0	(2)
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest rate swap contract [Member] | Net sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest rate swap contract [Member] | Cost of sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest rate swap contract [Member] | Foreign currency loss, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	0		0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest rate swap contract [Member] | Other income (expense), net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	0	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest rate swap contract [Member] | Interest expense, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net			18
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Cross-currency swap contract
Derivative Instruments, Gain (Loss) [Line Items]
Balance in accumulated other comprehensive (loss) income	0	0	0	$ (2,017)
Amounts recognized in other comprehensive (loss) income	0	0	5,108
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Cross-currency swap contract | Net sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Cross-currency swap contract | Cost of sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Cross-currency swap contract | Foreign currency loss, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	0		(4,896)
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Cross-currency swap contract | Other income (expense), net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	$ 0	$ 0
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Cross-currency swap contract | Interest expense, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net			$ 1,805

Note 10. Derivative Financial_5

Note 10. Derivative Financial Instruments (Details) - Risk Management € in Millions, ₨ in Millions, $ in Millions, $ in Millions, ¥ in Billions

12 Months Ended

Dec. 31, 2018USD ($)

Dec. 31, 2017USD ($)

Dec. 31, 2018AUD ($)

Dec. 31, 2018JPY (¥)

Aug. 31, 2018JPY (¥)

May 31, 2018AUD ($)

Dec. 31, 2017EUR (€)

Dec. 31, 2017AUD ($)

Dec. 31, 2017INR (₨)

Dec. 31, 2017JPY (¥)

Mar. 31, 2017AUD ($)

Mar. 31, 2017JPY (¥)

Foreign exchange forward contracts [Member]

Derivatives, Fair Value [Line Items]

Maximum Length of Time Hedged in Foreign Currency Cash Flow Hedge

6 months

9 months

Foreign exchange forward contracts [Member] | Cash Flow Hedging [Member]

Derivatives, Fair Value [Line Items]

Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months | $

$ 1.3

Foreign exchange forward contracts [Member] | Cash Flow Hedging [Member] | Australia, Dollars

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

$ 6.2

$ 8.8

Foreign exchange forward contracts [Member] | Cash Flow Hedging [Member] | India, Rupees

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

$ 74.1

₨ 4,730

Foreign exchange forward contracts [Member] | Cash Flow Hedging [Member] | Euro Member Countries, Euro

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

18.8

€ 15.7

Royal Solar Credit Facility [Member] | Interest rate swap contract [Member]

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

¥ 5.5

Derivative, basis spread on variable rate

0.65%

0.65%

0.65%

Derivative, fixed interest rate paid on swap

1.34%

1.34%

1.34%

Mashiko Credit Agreement [Member] | Interest rate swap contract [Member]

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

¥ 5.5

Derivative, fixed interest rate paid on swap

0.82%

Beryl Credit Facility [Member] | Interest rate swap contract [Member]

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

$ 72.9

$ 103.4

$ 42.4

Beryl Credit Facility [Member] | Minimum [Member] | Interest rate swap contract [Member]

Derivatives, Fair Value [Line Items]

Derivative, fixed interest rate paid on swap

2.0615%

Beryl Credit Facility [Member] | Maximum [Member] | Interest rate swap contract [Member]

Derivatives, Fair Value [Line Items]

Derivative, fixed interest rate paid on swap

3.202%

Manildra Credit Facility [Member] | Interest rate swap contract [Member]

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

48

$ 68.1

$ 12.8

Derivative, fixed interest rate paid on swap

3.13%

3.13%

Ishikawa Credit Agreement [Member] | Interest rate swap contract [Member]

Derivatives, Fair Value [Line Items]

Derivative, Notional Amount

$ 174.1

$ 115.7

¥ 19.2

¥ 12.8

¥ 5.7

Derivative, basis spread on variable rate

0.75%

0.75%

Derivative, fixed interest rate paid on swap

1.482%

1.482%

Note 10. Derivative Financial_6

Note 10. Derivative Financial Instruments (Details) - Transaction Exposure - Foreign exchange forward contracts [Member] - Not Designated as Hedging Instrument [Member] € in Millions, ₨ in Millions, ¥ in Millions, ¥ in Millions, RM in Millions, R$ in Millions, R in Millions, $ in Millions, $ in Millions, $ in Millions, $ in Millions, $ in Millions, $ in Millions

12 Months Ended

Dec. 31, 2018USD ($)

Dec. 31, 2017USD ($)

Dec. 31, 2018SGD ($)

Dec. 31, 2018EUR (€)

Dec. 31, 2018CLP ($)

Dec. 31, 2018BRL (R$)

Dec. 31, 2018MYR (RM)

Dec. 31, 2018AUD ($)

Dec. 31, 2018CAD ($)

Dec. 31, 2018MXN ($)

Dec. 31, 2018INR (₨)

Dec. 31, 2018JPY (¥)

Dec. 31, 2017SGD ($)

Dec. 31, 2017EUR (€)

Dec. 31, 2017CNY (¥)

Dec. 31, 2017CLP ($)

Dec. 31, 2017MYR (RM)

Dec. 31, 2017AUD ($)

Dec. 31, 2017CAD ($)

Dec. 31, 2017ZAR (R)

Dec. 31, 2017INR (₨)

Dec. 31, 2017JPY (¥)

Derivative [Line Items]

Maximum Remaining Maturity of Foreign Currency Derivatives

3 months

Australia, Dollars

Derivative [Line Items]

Derivative, Currency Bought

Australian dollar

Australian dollar

Derivative, Currency Sold

Australian dollar

Australian dollar

Brazil, Brazil Real

Derivative [Line Items]

Derivative, Currency Bought

Brazilian real

Canada, Dollars

Derivative [Line Items]

Derivative, Currency Sold

Canadian dollar

Canadian dollar

Chile, Pesos

Derivative [Line Items]

Derivative, Currency Sold

Chilean peso

Chilean peso

China, Yuan Renminbi

Derivative [Line Items]

Derivative, Currency Bought

Chinese yuan

Euro Member Countries, Euro

Derivative [Line Items]

Derivative, Currency Bought

Euro

Euro

Derivative, Currency Sold

Euro

Euro

India, Rupees

Derivative [Line Items]

Derivative, Currency Bought

Indian rupee

Derivative, Currency Sold

Indian rupee

Indian rupee

Japan, Yen

Derivative [Line Items]

Derivative, Currency Bought

Japanese yen

Derivative, Currency Sold

Japanese yen

Japanese yen

Malaysia, Ringgits

Derivative [Line Items]

Derivative, Currency Bought

Malaysian ringgit

Malaysian ringgit

Derivative, Currency Sold

Malaysian ringgit

Malaysian ringgit

Mexico, Pesos

Derivative [Line Items]

Derivative, Currency Sold

Mexican peso

Singapore, Dollars

Derivative [Line Items]

Derivative, Currency Bought

Singapore dollar

Derivative, Currency Sold

Singapore dollar

South Africa, Rand

Derivative [Line Items]

Derivative, Currency Bought

South African rand

Derivative, Currency Sold

South African rand

Long [Member] | Australia, Dollars

Derivative [Line Items]

Derivative, Notional Amount

$ 1.5

$ 9.9

$ 2.1

$ 12.7

Long [Member] | Brazil, Brazil Real

Derivative [Line Items]

Derivative, Notional Amount

2.2

R$ 8.5

Long [Member] | China, Yuan Renminbi

Derivative [Line Items]

Derivative, Notional Amount

2.1

¥ 13.8

Long [Member] | Euro Member Countries, Euro

Derivative [Line Items]

Derivative, Notional Amount

131.9

181.6

€ 115.2

€ 151.4

Long [Member] | India, Rupees

Derivative [Line Items]

Derivative, Notional Amount

10.1

₨ 645.7

Long [Member] | Japan, Yen

Derivative [Line Items]

Derivative, Notional Amount

8.4

¥ 931.6

Long [Member] | Malaysia, Ringgits

Derivative [Line Items]

Derivative, Notional Amount

8.3

7.7

RM 34.3

RM 31

Long [Member] | Singapore, Dollars

Derivative [Line Items]

Derivative, Notional Amount

2.8

$ 3.8

Long [Member] | South Africa, Rand

Derivative [Line Items]

Derivative, Notional Amount

1

R 12.5

Short [Member] | Australia, Dollars

Derivative [Line Items]

Derivative, Notional Amount

37.3

44.4

$ 52.9

$ 56.8

Short [Member] | Canada, Dollars

Derivative [Line Items]

Derivative, Notional Amount

2.1

1.4

$ 2.9

$ 1.7

Short [Member] | Chile, Pesos

Derivative [Line Items]

Derivative, Notional Amount

5.1

16.6

$ 3,506.6

$ 10,180.9

Short [Member] | Euro Member Countries, Euro

Derivative [Line Items]

Derivative, Notional Amount

219.7

231.7

€ 191.8

€ 193.2

Short [Member] | India, Rupees

Derivative [Line Items]

Derivative, Notional Amount

11.3

131.1

₨ 789.2

₨ 8,376

Short [Member] | Japan, Yen

Derivative [Line Items]

Derivative, Notional Amount

216.2

212.6

¥ 23,858.8

¥ 23,922.2

Short [Member] | Malaysia, Ringgits

Derivative [Line Items]

Derivative, Notional Amount

12.9

83.1

RM 53.8

RM 336.5

Short [Member] | Mexico, Pesos

Derivative [Line Items]

Derivative, Notional Amount

$ 1.9

$ 37.3

Short [Member] | Singapore, Dollars

Derivative [Line Items]

Derivative, Notional Amount

2.3

$ 3.1

Short [Member] | South Africa, Rand

Derivative [Line Items]

Derivative, Notional Amount

$ 5

R 61.1

Note 11. Fair Value Measureme_3

Note 11. Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Assets:
Marketable securities	$ 1,143,704	$ 720,379
Restricted investments	179,000	373,961
Foreign debt [Member]
Assets:
Marketable securities	318,646	238,858
Foreign government obligations [Member]
Assets:
Marketable securities	98,621	152,850
U.S debt [Member]
Assets:
Marketable securities	44,468	73,671
Time deposits [Member]
Assets:
Marketable securities	681,969	255,000
Fair Value, Measurements, Recurring [Member]
Assets:
Restricted investments	179,000	373,961
Derivative assets	2,364	4,303
Total assets	1,525,856	1,224,228
Liabilities:
Derivative liabilities	16,499	33,229
Fair Value, Measurements, Recurring [Member] | Foreign debt [Member]
Assets:
Marketable securities	318,646	238,858
Fair Value, Measurements, Recurring [Member] | Foreign government obligations [Member]
Assets:
Marketable securities	98,621	152,850
Fair Value, Measurements, Recurring [Member] | U.S debt [Member]
Assets:
Marketable securities	44,468	73,671
Fair Value, Measurements, Recurring [Member] | Time deposits [Member]
Assets:
Marketable securities	681,969	255,000
Fair Value, Measurements, Recurring [Member] | Money market funds
Assets:
Cash equivalents	200,788	125,585
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Restricted investments	0	0
Derivative assets	0	0
Total assets	882,757	380,585
Liabilities:
Derivative liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Foreign debt [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Foreign government obligations [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S debt [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Time deposits [Member]
Assets:
Marketable securities	681,969	255,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Money market funds
Assets:
Cash equivalents	200,788	125,585
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Restricted investments	179,000	373,961
Derivative assets	2,364	4,303
Total assets	643,099	843,643
Liabilities:
Derivative liabilities	16,499	33,229
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Foreign debt [Member]
Assets:
Marketable securities	318,646	238,858
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Foreign government obligations [Member]
Assets:
Marketable securities	98,621	152,850
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S debt [Member]
Assets:
Marketable securities	44,468	73,671
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Time deposits [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Money market funds
Assets:
Cash equivalents	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets:
Restricted investments	0	0
Derivative assets	0	0
Total assets	0	0
Liabilities:
Derivative liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Foreign debt [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Foreign government obligations [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S debt [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Time deposits [Member]
Assets:
Marketable securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Money market funds
Assets:
Cash equivalents	$ 0	$ 0

Note 11. Fair Value Measureme_4

Note 11. Fair Value Measurements (Details) - Balance Sheet Grouping - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Notes receivable - noncurrent	$ 8,017	$ 10,495
Notes receivable, affiliate - current	0	20,411
Notes receivable, affiliates - noncurrent	22,832	48,370
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term Debt, including current maturities	479,157
Reported Value Measurement [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Notes receivable - noncurrent	8,017	10,495
Notes receivable, affiliate - current	0	20,411
Notes receivable, affiliates - noncurrent	22,832	48,370
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term Debt, including current maturities	479,157	406,388
Estimate of Fair Value Measurement [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Notes receivable - noncurrent	8,010	10,516
Notes receivable, affiliate - current	0	23,317
Notes receivable, affiliates - noncurrent	24,295	47,441
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term Debt, including current maturities	$ 470,124	$ 416,486

Note 12. Equity Method Invest_3

Note 12. Equity Method Investments (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 29, 2016	Nov. 30, 2014
Schedule of Equity Method Investments [Line Items]
Equity Method Investments			$ 3,186	$ 217,230
Proceeds from sales of equity method investments			247,595	0	$ 291,502
Equity in earnings, net of tax			34,620	4,266	144,306
Proceeds from Equity Method Investments, Distributions			12,394	23,042	18,562
Net sales			2,244,044	2,941,324	2,904,563
Notes receivable, affiliates - noncurrent			22,832	48,370
Payments received on notes receivable, affiliates			48,729	1,740	3,053
Notes receivable, affiliate - current			0	20,411
Equity Method Investment, Other than Temporary Impairment			3,500	2,000	600
Summarized financial information, net sales			28,736	70,089	125,643
Summarized financial information, operating (loss) income			(38,606)	24,661	55,266
Summarized financial information, net (loss) income			(39,280)	46,713	63,893
Summarized financial information, net (loss) income attributable to equity method investees			(45,228)	53,183	190,240
Summarized financial information, current assets			0	36,744
Summarized financial information, long-term assets			0	1,573,115
Summarized financial information, current liabilities			0	7,648
Summarized financial information, long-term liabilities			0	706,885
Summarized financial information, noncontrolling interests, including redeemable noncontrolling interests			0	72,945
O&M Services [Member]
Schedule of Equity Method Investments [Line Items]
Net sales			103,186	101,024	93,476
Solar Modules [Member]
Schedule of Equity Method Investments [Line Items]
Net sales			502,001	806,398	675,453
Maryland Solar Project [Member]
Schedule of Equity Method Investments [Line Items]
Net sales		$ 32,000
Sale Leaseback Transaction, Amount Due under Financing Arrangement				35,000
8point3 Operating Company, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments			0	199,477
Proceeds from sales of equity method investments		240,000
Equity in earnings, net of tax			39,700	9,800	32,600
Equity Method Investment, Realized Gain on Disposal		40,300
Gain on Sale of Previously Unissued Stock by Equity Investee					$ 8,500
Sale of Stock, Number of Shares Issued in Transaction					8,050,000
Proceeds from Equity Method Investments, Distributions			12,400	23,000	$ 5,300
Notes receivable, affiliates - noncurrent				48,400	50,000
Payments received on notes receivable, affiliates		$ 47,800
8point3 Energy Partners LP [Member] | O&M Services [Member]
Schedule of Equity Method Investments [Line Items]
Revenue from Related Parties			5,600	11,000	$ 6,100
Desert Stateline Holdings, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage Sold					34.00%
Clean Energy Collective, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments			0	6,521
Equity in earnings, net of tax			4,300	2,600	$ 3,600
Notes receivable, affiliates - noncurrent			$ 22,800
Note Receivable Interest Rate							16.00%
Convertible Notes Receivable Interest Rate						10.00%
Notes receivable, affiliate - current				20,400
Equity Method Investment, Other than Temporary Impairment	$ 3,500
Equity Method Investment, Ownership Percentage			25.00%
Clean Energy Collective, LLC [Member] | Solar Modules [Member]
Schedule of Equity Method Investments [Line Items]
Revenue from Related Parties				7,600
Clean Energy Collective, LLC Warrant [Member]
Schedule of Equity Method Investments [Line Items]
Other than temporary impairment of warrant	$ 1,800
Other Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments			$ 3,186	$ 11,232

Note 13. Solar Module Collect_2

Note 13. Solar Module Collection and Recycling Liability (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Solar Module Collection and Recycling Liability [Abstract]
Change in estimate of module collection and recycling liability	$ 34,200	$ 15,800
Accrued solar module collection and recycling liability	134,442	166,609
Solar module collection and recycling expense, cost of sales	(25,000)	(13,200)
Solar module collection and recycling expense, accretion expense	$ (2,900)	$ 3,900	$ 6,100
Percentage increase in annualized inflation rate	1.00%
Estimated increase in solar module collection recycling liability from sensitivity analysis	$ 25,700
Percentage decrease in annualized inflation rate	1.00%
Estimated decrease in solar module collection recycling liability from sensitivity analysis	$ 21,700

Note 14. Debt (Details)

Note 14. Debt (Details) $ in Thousands, $ in Millions, ₨ in Billions, ¥ in Billions

1 Months Ended

12 Months Ended

May 31, 2018USD ($)

Dec. 31, 2018USD ($)

Dec. 31, 2017USD ($)

Dec. 31, 2016USD ($)

Dec. 31, 2018AUD ($)

Dec. 31, 2018JPY (¥)

Oct. 31, 2018USD ($)

Oct. 31, 2018AUD ($)

Aug. 31, 2018USD ($)

Jun. 30, 2018USD ($)

Jun. 30, 2018AUD ($)

Mar. 31, 2018USD ($)

Mar. 31, 2018INR (₨)

Mar. 31, 2018JPY (¥)

Feb. 28, 2018USD ($)

Dec. 31, 2017INR (₨)

Jun. 30, 2017USD ($)

Jun. 30, 2017JPY (¥)

Mar. 31, 2017USD ($)

Mar. 31, 2017AUD ($)

Dec. 31, 2016INR (₨)

Dec. 31, 2016JPY (¥)

Sep. 30, 2015USD ($)

Sep. 30, 2015JPY (¥)

Mar. 31, 2015USD ($)

Mar. 31, 2015INR (₨)

Long-term Debt [Abstract]

Long-term debt, gross

$ 479,157

$ 406,544

Less: unamortized discount and issuance costs

(12,366)

(13,004)

Total long-term debt

466,791

393,540

Less: current portion

(5,570)

(13,075)

Noncurrent portion

461,221

380,465

Interest Paid

16,600

10,200

$ 4,300

Long-term Debt, Fiscal Year Maturity [Abstract]

Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months

5,673

Long-term Debt, Maturities, Repayments of Principal in Year Two

26,935

Long-term Debt, Maturities, Repayments of Principal in Year Three

66,014

Long-term Debt, Maturities, Repayments of Principal in Year Four

12,221

Long-term Debt, Maturities, Repayments of Principal in Year Five

71,620

Long-term Debt, Maturities, Repayments of Principal after Year Five

296,694

Total long-term debt future principal payments

$ 479,157

Revolving Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

USD

Revolving credit facility

$ 0

0

Line of Credit Facility, Current Borrowing Capacity

500,000

Line of Credit Facility, Maximum Borrowing Capacity

750,000

Letters of Credit Outstanding, Amount

$ 66,000

57,500

Line of Credit Facility, Unused Capacity, Commitment Fee Percentage

0.30%

Fronting fee

0.125%

Line of Credit Facility, Letter of Credit Sub-Limit

$ 400,000

Debt Instrument, Interest Rate, Stated Percentage

4.50%

4.50%

4.50%

Debt Instrument, Description of Variable Rate Basis

Borrowings under the credit facility bear interest at (i) London Interbank Offered Rate (“LIBOR”), adjusted for Eurocurrency reserve requirements, plus a margin of 2.00% or (ii) a base rate as defined in the credit agreement plus a margin of 1.00% depending on the type of borrowing requested

Revolving Credit Facility [Member] | Minimum [Member]

Long-term Debt [Abstract]

Debt Instrument, Basis Spread on Variable Rate

1.00%

Revolving Credit Facility [Member] | Maximum [Member]

Long-term Debt [Abstract]

Debt Instrument, Basis Spread on Variable Rate

2.00%

Luz del Norte Credit Facilities [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

USD

Long-term debt, gross

$ 188,849

185,675

Luz del Norte Credit Facilities [Member] | OPIC [Member] | Parque Solar Fotovoltaico Luz del Norte SpA [Member]

Long-term Debt [Abstract]

Long-term debt, gross

141,400

139,000

Luz del Norte Credit Facilities [Member] | IFC [Member] | Parque Solar Fotovoltaico Luz del Norte SpA [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 47,400

46,600

Luz del Norte Credit Facilities [Member] | OPIC and IFC [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Fixed Rate Basis

Fixed rate loans at bank rate plus 3.50%

Debt Instrument, Description of Variable Rate Basis

Variable rate loans at 91-Day U.S. Treasury Bill Yield or LIBOR plus 3.50%

Debt Instrument, Basis Spread on Fixed Rate

3.50%

Debt Instrument, Basis Spread on Variable Rate

3.50%

Luz del Norte Credit Facilities [Member] | Fixed Rate Term Loan [Member] | OPIC and IFC [Member] | Parque Solar Fotovoltaico Luz del Norte SpA [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 161,100

Luz del Norte Credit Facilities [Member] | Variable Rate Term Loan [Member] | OPIC and IFC [Member] | Parque Solar Fotovoltaico Luz del Norte SpA [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 27,700

Ishikawa Credit Agreement [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

JPY

Long-term debt, gross

$ 157,834

121,446

Ishikawa Credit Agreement [Member] | Mizuho Bank [Member] | FS Japan Project 12 GK [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 157,800

121,400

Line of Credit Facility, Current Borrowing Capacity

247,400

¥ 27.3

Ishikawa Credit Agreement [Member] | Senior Loan Facility [Member] | Mizuho Bank [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

Senior loan facility at 6-month TIBOR plus 0.75% (2)

Debt Instrument, Basis Spread on Variable Rate

0.75%

Ishikawa Credit Agreement [Member] | Senior Loan Facility [Member] | Mizuho Bank [Member] | FS Japan Project 12 GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

217,500

24

Ishikawa Credit Agreement [Member] | Consumption Tax Facility [Member] | Mizuho Bank [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

Consumption tax facility at 3-month TIBOR plus 0.5%

Debt Instrument, Basis Spread on Variable Rate

0.50%

Ishikawa Credit Agreement [Member] | Consumption Tax Facility [Member] | Mizuho Bank [Member] | FS Japan Project 12 GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

19,000

2.1

Ishikawa Credit Agreement [Member] | Letter of Credit Facility [Member] | Mizuho Bank [Member] | FS Japan Project 12 GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

10,900

¥ 1.2

Japan Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

JPY

Long-term debt, gross

$ 0

10,710

Japan Credit Facility [Member] | Mizuho Bank [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

1-month TIBOR plus 0.5%

Debt Instrument, Basis Spread on Variable Rate

0.50%

Japan Credit Facility [Member] | Mizuho Bank [Member] | First Solar Japan GK [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 0

10,700

Line of Credit Facility, Current Borrowing Capacity

$ 36,300

¥ 4

Tochigi Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

JPY

Long-term debt, gross

$ 25,468

0

Tochigi Credit Facility [Member] | Mizuho Bank [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

3-month TIBOR plus 1.0%

Debt Instrument, Basis Spread on Variable Rate

1.00%

Tochigi Credit Facility [Member] | Mizuho Bank [Member] | First Solar Japan GK [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 25,500

0

Line of Credit Facility, Current Borrowing Capacity

$ 63,400

¥ 7

Mashiko Credit Agreement [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

JPY

Long-term debt, gross

$ 0

0

Mashiko Credit Agreement [Member] | Mizuho Bank [Member] | FS Japan Project 14 GK [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 57,200

Line of Credit Facility, Current Borrowing Capacity

$ 83,400

¥ 9.2

Mashiko Credit Agreement [Member] | Senior Loan Facility [Member] | Mizuho Bank [Member] | FS Japan Project 14 GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

73,400

8.1

Mashiko Credit Agreement [Member] | Consumption Tax Facility [Member] | Mizuho Bank [Member] | FS Japan Project 14 GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

6,300

0.7

Mashiko Credit Agreement [Member] | Letter of Credit Facility [Member] | Mizuho Bank [Member] | FS Japan Project 14 GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

3,600

¥ 0.4

Royal Solar Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

JPY

Long-term debt, gross

$ 0

0

Royal Solar Credit Facility [Member] | Shinsei Bank, Ltd. [Member] | Royal Solar GK [Member]

Long-term Debt [Abstract]

Long-term debt, gross

67,200

Line of Credit Facility, Current Borrowing Capacity

106,900

¥ 11.8

Royal Solar Credit Facility [Member] | Consumption Tax Facility [Member] | Shinsei Bank, Ltd. [Member] | Royal Solar GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

8,200

0.9

Royal Solar Credit Facility [Member] | Term Loan Facility [Member] | Shinsei Bank, Ltd. [Member] | Royal Solar GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

95,200

10.5

Royal Solar Credit Facility [Member] | Debt Service Reserve Facility [Member] | Shinsei Bank, Ltd. [Member] | Royal Solar GK [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

$ 3,600

¥ 0.4

Marikal Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

INR

Long-term debt, gross

$ 0

7,384

Marikal Credit Facility [Member] | Axis Bank [Member] | Marikal Solar Parks Private Limited [Member]

Long-term Debt [Abstract]

Long-term debt, gross

7,400

Line of Credit Facility, Current Borrowing Capacity

$ 7,800

₨ 0.5

Repayments of Debt

$ 6,800

Hindupur Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

INR

Long-term debt, gross

$ 0

18,722

Hindupur Credit Facility [Member] | Yes Bank Limited [Member] | Hindupur Solar Parks Private Limited [Member]

Long-term Debt [Abstract]

Long-term debt, gross

18,700

$ 17,000

Line of Credit Facility, Current Borrowing Capacity

61,400

₨ 4.3

Letters of Credit Outstanding, Amount

41,400

₨ 2.9

Line of Credit Facility, Letter of Credit Sub-Limit

$ 45,700

₨ 3.2

Anantapur Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

INR

Long-term debt, gross

$ 16,101

0

Anantapur Credit Facility [Member] | J.P. Morgan Securities India Private Limited [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

INR overnight indexed swap rate plus 1.5%

Debt Instrument, Basis Spread on Variable Rate

1.50%

Anantapur Credit Facility [Member] | J.P. Morgan Securities India Private Limited [Member] | Anantapur Solar Parks Private Limited [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 16,100

Line of Credit Facility, Current Borrowing Capacity

17,100

₨ 1.2

Tungabhadra Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

INR

Long-term debt, gross

$ 13,934

0

Tungabhadra Credit Facility [Member] | J.P. Morgan Securities India Private Limited [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

INR overnight indexed swap rate plus 1.5%

Debt Instrument, Basis Spread on Variable Rate

1.50%

Tungabhadra Credit Facility [Member] | J.P. Morgan Securities India Private Limited [Member] | Tungabhadra Solar Parks Private Limited [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 13,900

Line of Credit Facility, Current Borrowing Capacity

$ 14,300

₨ 1

Manildra Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

AUD

Long-term debt, gross

$ 0

62,451

Manildra Credit Facility [Member] | Société Générale S.A. and The Bank of Tokyo-Mitsubishi UFJ, Ltd. [Member] | Manildra Finco Pty Ltd [Member]

Long-term Debt [Abstract]

Long-term debt, gross

62,500

$ 56,100

Line of Credit Facility, Current Borrowing Capacity

$ 57,600

$ 81.7

Manildra Credit Facility [Member] | Construction Loans [Member] | Société Générale S.A. and The Bank of Tokyo-Mitsubishi UFJ, Ltd. [Member] | Manildra Finco Pty Ltd [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

53,400

75.7

Manildra Credit Facility [Member] | Goods and Service Tax Facility [Member] | Société Générale S.A. and The Bank of Tokyo-Mitsubishi UFJ, Ltd. [Member] | Manildra Finco Pty Ltd [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

$ 4,200

$ 6

Beryl Credit Facility [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

AUD

Long-term debt, gross

$ 76,971

0

Beryl Credit Facility [Member] | MUFG Bank, Ltd.; Société Générale, Hong Kong Branch; and Mizuho Bank, Ltd. [Member] | FS NSW Project No 1 Finco Pty Ltd [Member]

Long-term Debt [Abstract]

Long-term debt, gross

$ 77,000

Line of Credit Facility, Current Borrowing Capacity

$ 96,200

$ 136.4

$ 103,200

$ 146.4

Beryl Credit Facility [Member] | Construction Loans [Member] | MUFG Bank, Ltd.; Société Générale, Hong Kong Branch; and Mizuho Bank, Ltd. [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

Construction loan facility at 1-month BBSY plus 1.75% (2)

Debt Instrument, Basis Spread on Variable Rate

1.75%

Beryl Credit Facility [Member] | Construction Loans [Member] | MUFG Bank, Ltd.; Société Générale, Hong Kong Branch; and Mizuho Bank, Ltd. [Member] | FS NSW Project No 1 Finco Pty Ltd [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

$ 88,400

$ 125.4

Beryl Credit Facility [Member] | Goods and Service Tax Facility [Member] | MUFG Bank, Ltd.; Société Générale, Hong Kong Branch; and Mizuho Bank, Ltd. [Member]

Long-term Debt [Abstract]

Debt Instrument, Description of Variable Rate Basis

GST facility at 1-month BBSY plus 1.00%

Debt Instrument, Basis Spread on Variable Rate

1.00%

Beryl Credit Facility [Member] | Goods and Service Tax Facility [Member] | MUFG Bank, Ltd.; Société Générale, Hong Kong Branch; and Mizuho Bank, Ltd. [Member] | FS NSW Project No 1 Finco Pty Ltd [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

$ 4,900

7

Beryl Credit Facility [Member] | Letter of Credit Facility [Member] | MUFG Bank, Ltd.; Société Générale, Hong Kong Branch; and Mizuho Bank, Ltd. [Member] | FS NSW Project No 1 Finco Pty Ltd [Member]

Long-term Debt [Abstract]

Line of Credit Facility, Current Borrowing Capacity

$ 2,800

$ 4

Capital Lease Obligations [Member]

Long-term Debt [Abstract]

Debt Instrument, Currency

Various

Long-term debt, gross

$ 0

$ 156

Note 15. Commitments and Cont_3

Note 15. Commitments and Contingencies (Details) - Commercial Commitments - USD ($) $ in Thousands	Dec. 31, 2018	Feb. 28, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Bank Guarantees and Letters of Credit	$ 600
Surety Bonds	57,800
Surety Bond Capacity	658,500
Commercial letter of credit liability	0		$ 43,396
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Letter of Credit Sub-Limit	400,000
Letters of Credit Outstanding, Amount	66,000		57,500
Letters of Credit, Remaining Borrowing Capacity	334,000
Bilateral Facilities [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount	281,100
Cash Collateral for Borrowed Securities	44,400
Bilateral Facilities, Bank Guarantees and Letter of Credit [Member]
Debt Instrument [Line Items]
Letters of Credit, Remaining Borrowing Capacity	$ 157,900
Hindupur Credit Facility [Member]
Debt Instrument [Line Items]
Commercial letter of credit liability		$ 43,300	$ 43,396

Note 15. Commitments and Cont_4

Note 15. Commitments and Contingencies (Details) - Lease Commitments - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, Future Minimum Payments, Due Next Twelve Months	$ 13,839
Operating Leases, Future Minimum Payments, Due in Two Years	9,031
Operating Leases, Future Minimum Payments, Due in Three Years	8,309
Operating Leases, Future Minimum Payments, Due in Four Years	7,824
Operating Leases, Future Minimum Payments, Due in Five Years	7,749
Operating Leases, Future Minimum Payments, Due Thereafter	100,062
Total Minimum Operating Lease Payments	146,814
Rent Expense	$ 18,900	$ 22,100	$ 24,500

Note 15. Commitments and Cont_5

Note 15. Commitments and Contingencies (Details) - Purchase Commitments $ in Millions	Dec. 31, 2018USD ($)
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 1,400
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months	875.7
Capital Addition Purchase Commitments [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 335.6

Note 15. Commitments and Cont_6

Note 15. Commitments and Contingencies (Details) - Product Warranties - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Movement in Standard Product Warranty Accrual [Roll Forward]
Product warranty liability, beginning of period	$ 224,274	$ 252,408	$ 231,751
Accruals for new warranties issued	14,132	23,313	35,256
Settlements	(11,851)	(11,329)	(16,266)
Changes in estimate of product warranty liability	(5,863)	(40,118)	1,667
Product warranty liability, end of period	220,692	224,274	252,408
Current portion of warranty liability	27,657	28,767	40,079
Noncurrent portion of warranty liability	$ 193,035	195,507	$ 212,329
Reduction in the estimated replacement cost of modules		$ 31,300
Percentage Point Change in Estimated Rate of Return of Module Warranty	1.00%
Estimated Change in Module Warranty from Sensitivity Analysis	$ 74,600
Percentage Point Change in Estimated Rate of Return of Balance of Systems Warranty	1.00%
Minimum [Member]
Movement in Standard Product Warranty Accrual [Roll Forward]
Estimated rate of return for module warranty	1.00%
Maximum [Member]
Movement in Standard Product Warranty Accrual [Roll Forward]
Estimated rate of return for module warranty	3.00%

Note 15. Commitments and Cont_7

Note 15. Commitments and Contingencies (Details) - Performance Guarantees - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Energy Performance Testing Liability	$ 0.4	$ 2.1

Note 15. Commitments and Cont_8

Note 15. Commitments and Contingencies (Details) - Indemnifications - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Indemnification liabilities, current	$ 0	$ 2,876
Indemnification liabilities, noncurrent	3,000	$ 4,900
Indemnification liabilities, maximum exposure	125,300
Indemnification liabilities, potential insurance recoveries	$ 84,900

Note 15. Commitments and Cont_9

Note 15. Commitments and Contingencies (Details) - Contingent Consideration - USD ($) $ in Millions	1 Months Ended
	Oct. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition, Contingent Consideration [Line Items]
Project Acquisition, Contingent Consideration Liability, Current		$ 0.7	$ 4.4
Project Acquisition, Contingent Consideration Liability, Noncurrent		$ 2.3	3.2
Enki Technology [Member]
Business Acquisition, Contingent Consideration [Line Items]
Payment for contingent consideration liability	$ 3.5
Business combination, contingent consideration liability, current			$ 1.8

Note 16. Revenue from Contrac_3

Note 16. Revenue from Contracts with Customers (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)Projects	Dec. 31, 2017USD ($)Projects	Dec. 31, 2016USD ($)Projects
Revenue from Contracts with Customers [Line Items]
Net sales	$ 2,244,044	$ 2,941,324	$ 2,904,563
Project Change in Estimate Disclosure Threshold	$ 1,000
Number of Projects with Changes in Estimates | Projects	24	5	12
Increase (Decrease) in Revenue from Net Changes in Transaction Price	$ 63,361	$ 3,579	$ (67,292)
Increase in Revenue from Net Changes in Input Cost Estimates	1,548	5,047	164,920
Net Increase in Revenue from Net Changes in Estimates	$ 64,909	$ 8,626	$ 97,628
Net Change in Estimate as a Percentage of Aggregate Revenue	0.60%	0.60%	1.60%
Increase (Decrease) in Revenue from Net Changes in Indirect Tax Estimates	$ 54,600
Accounts receivable, unbilled	441,666	$ 172,594
Retainage	16,500	2,014
Accounts receivable, unbilled and retainage	458,166	174,608
Contract Asset, Net Change	$ 283,558
Contract Asset, Percent Change	162.00%
Deferred revenue	$ 177,769	145,073
Contract Liability, Net Change	$ 32,696
Contract Liability, Percent Change	23.00%
Deferred revenue, noncurrent	$ 48,014	63,257
Sales Revenue Net, from Beginning Contract Liability	128,700	308,600
Solar Modules [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	502,001	806,398	$ 675,453
Remaining Performance Obligation, Transaction Price	3,200,000
Solar Power Systems [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	1,244,175	1,927,122	1,131,961
EPC Services [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	347,560	45,525	892,814
O&M Services [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	103,186	101,024	93,476
Remaining Performance Obligation, Transaction Price	$ 500,000
Remaining Performance Obligation, Period of Recognition	11 years 6 months
Module Plus [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	$ 0	3,236	84,926
Energy Generation [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	47,122	$ 58,019	$ 25,933
Solar Power Systems, Sales of and EPC Services [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Transaction Price	$ 700,000
Solar Power Systems, Sales of and EPC Services [Member] | Phoebe [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	12.00%
Solar Power Systems, Sales of and EPC Services [Member] | GA Solar 4 [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	11.00%
Solar Power Systems, Sales of and EPC Services [Member] | Rosamond [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	57.00%
Solar Power Systems, Sales of and EPC Services [Member] | Willow Springs [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	96.00%
Solar Power Systems, Sales of and EPC Services [Member] | Grange Hall [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	98.00%
Solar Power Systems, Sales of and EPC Services [Member] | Peace Creek [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	70.00%
Solar Power Systems, Sales of and EPC Services [Member] | Troy Solar [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	0.00%
Solar Power Systems, Sales of and EPC Services [Member] | Lake Hancock [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Percent of Revenue Recognized	34.00%

Note 17. Stockholders' Equity_2

Note 17. Stockholders' Equity (Details) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Class of Stock Disclosures [Abstract]
Preferred Stock, Shares Authorized	30,000,000
Preferred Stock, Par Value	$ 0.001
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Par Value	$ 0.001	$ 0.001
Common Stock, Shares Issued	104,885,261	104,468,460
Common Stock, Shares Outstanding	104,885,261	104,468,460

Note 18. Share-Based Compensa_3

Note 18. Share-Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	$ 34,154	$ 35,121	$ 28,712
Share-based Compensation Expense, Gross	33,860	34,460	28,085
Net amount released from inventory	294	661	627
Share-based compensation, capitalized in inventory	1,800	2,100
Share-based compensation, nonvested awards, total compensation cost not yet recognized	$ 37,600
Share-based compensation, unrecognized compensation costs on nonvested awards, weighted average period of recognition (in years)	1 year 1 month
Share-based Compensation, Tax Benefit from Compensation Expense	$ 9,900	6,200	32,900
Restricted and performance stock units [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	32,223	32,309	25,076
Unrestricted stock [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	1,637	1,757	1,677
Stock purchase plan [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	0	394	1,332
Cost of sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	6,422	6,809	7,598
Selling, general and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	21,646	22,165	17,830
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	5,714	5,740	3,284
Production start-up [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-Based Compensation Expense	$ 372	$ 407	$ 0

Note 18. Share-Based Compensa_4

Note 18. Share-Based Compensation (Details) - RSUs - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restricted and performance stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested restricted stock units at beginning of period (shares)	2,302,906
Unvested restricted stock units at beginning of period (weighted average gant-date fair value)	$ 38.55
Restricted stock units granted (shares)	739,855
Restricted stock units granted (weighted average grant-date fair value)	$ 67.44	$ 32.81	$ 59.64
Restricted stock units vested (shares)	(490,682)
Restricted stock units vested (weighted average grant-date fair value)	$ 44.46
Restricted stock units forfeited (shares)	(77,792)
Restricted stock units forfeited (weighted average grant-date fair value)	$ 51.04
Unvested restricted stock units at end of period (shares)	2,474,287	2,302,906
Unvested restricted stock units at end of period (weighted average grant-date fair value)	$ 45.63	$ 38.55
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 32.2	$ 14.1	$ 131
Omnibus Incentive Compensation Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2,960,873

Note 18. Share-Based Compensa_5

Note 18. Share-Based Compensation (Details) - Stock Awards - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Expense	$ 34,154	$ 35,121	$ 28,712
Unrestricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrestricted stock units granted (shares)	31,190	42,773	38,429
Share-Based Compensation Expense	$ 1,637	$ 1,757	$ 1,677

Note 18. Share-Based Compensa_6

Note 18. Share-Based Compensation (Details) - Stock Purchase Plan	1 Months Ended	3 Months Ended
	Apr. 30, 2017	Mar. 31, 2017
Stock purchase plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date	4.00%	15.00%

Note 19. Income Taxes (Details)

Note 19. Income Taxes (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	May 31, 2017	Jul. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investments, Owned, Federal Income Tax Note [Line Items]
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Provisional Income Tax Expense (Benefit)			$ (2,300)	$ 6,600
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense (Benefit)			(8,100)	401,500
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability			$ 81,200
Tax Cuts and Jobs Act of 2017, Measurement Period Adjustments Effect on Tax Rate, Percent			9.20%
Foreign-Derived Intangible Income Deduction Limit, Percent			37.50%
Income (Loss) before Taxes and Equity in Earnings [Abstract]
U.S. income			$ (49,353)	(22,868)	$ (426,791)
Non-U.S. income			162,500	224,983	(110,460)
Income (loss) before taxes and equity in earnings			113,147	202,115	(537,251)
Current (Benefit) Expense [Abstract]
Federal			(44,267)	116,956	(14,389)
State			(13,568)	3,009	1,303
Foreign			8,788	11,099	(29,009)
Total current (benefit) expense			(49,047)	131,064	(42,095)
Deferred Expense [Abstract]
Federal			31,530	226,570	90,319
State			2,387	5,335	(9,536)
Foreign			18,571	9,027	(15,521)
Total deferred expense			52,488	240,932	65,262
Total income tax expense			3,441	371,996	23,167
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Statutory income tax expense (benefit) ($)			$ 23,761	$ 70,740	$ (188,038)
Statutory income tax expense (benefit) (%)			21.00%	35.00%	35.00%
Provisional effect of Tax Act ($)			$ 0	$ 408,090	$ 0
Provisional effect of Tax Act (%)			0.00%	201.90%	0.00%
Changes in valuation allowance ($)			$ 19,064	$ 9,534	$ 2,412
Changes in valuation allowance (%)			16.80%	4.70%	(0.40%)
Foreign tax rate differential ($)			$ 14,117	$ (22,048)	$ 6,833
Foreign tax rate differential (%)			12.50%	(10.90%)	(1.30%)
State tax, net of federal benefit ($)			$ (7,580)	$ 4,397	$ (8,655)
State tax, net of federal benefit (%)			(6.70%)	2.20%	1.60%
Non-deductible expenses ($)			$ 4,636	$ 2,703	$ 324
Non-deductible expenses (%)			4.10%	1.30%	0.00%
Share-based compensation ($)			$ (2,105)	$ 1,161	$ (23,283)
Share-based compensation (%)			(1.90%)	0.60%	4.30%
Change in tax contingency ($)			$ (6,273)	$ 959	$ (34,541)
Change in tax contingency (%)			(5.50%)	0.50%	6.40%
Foreign dividend income ($)			$ 16,570	$ 540	$ 248,013
Foreign dividend income (%)			14.60%	0.30%	(46.20%)
Goodwill ($)			$ 0	$ 0	$ 22,468
Goodwill (%)			0.00%	0.00%	(4.20%)
Tax credits ($)			$ (8,431)	$ (18,445)	$ (15,435)
Tax credits (%)			(7.50%)	(9.10%)	2.90%
Return to provision adjustments ($)			$ (25,307)	$ (35,191)	$ 11,757
Return to provision adjustments (%)			(22.30%)	(17.40%)	(2.20%)
Effect of tax holiday ($)			$ (26,277)	$ (46,643)	$ 4,640
Effect of tax holiday (%)			(23.20%)	(23.10%)	(0.90%)
Other ($)			$ 1,266	$ (3,801)	$ (3,328)
Other (%)			1.10%	(1.90%)	0.70%
Reported income tax expense (%)			3.00%	184.10%	(4.30%)
Income Taxes Paid, Net			$ 58,800	$ 1,200	$ 1,900
Deferred tax assets [Abstract]
Net operating losses			108,149	124,281
Accrued expenses			55,754	62,345
Property, plant and equipment			18,796	35,104
Compensation			18,564	9,442
Goodwill			9,223	12,140
Long-term contracts			4,967	4,554
Inventory			4,079	7,601
Capitalized interest			2,948	0
Equity in earnings			2,693	0
Deferred expenses			2,165	2,057
Other			17,373	12,584
Deferred tax assets, gross			244,711	270,108
Valuation allowance			(159,546)	(143,818)	$ (123,936)	$ (121,524)
Deferred tax assets, net of valuation allowance			85,165	126,290
Deferred tax liabilities [Abstract]
Restricted investments and derivatives			(7,586)	(10,680)
Acquisition accounting / basis difference			(5,420)	(5,880)
Investments in foreign subsidiaries			(4,425)	(9,555)
Equity in earnings			0	(40,339)
Capitalized interest			0	(1,722)
Other			(3,093)	(7,541)
Deferred tax liabilities			(20,524)	(75,717)
Net deferred tax assets and liabilities			$ 64,641	$ 50,573
Domestic Tax Authority [Member]
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ (42,100)
Foreign Tax Authority
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Tax Adjustments, Settlements, and Unusual Provisions		$ (35,400)

Note 19. Income Taxes (Detail_2

Note 19. Income Taxes (Details) - Valuation Allowance - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation Of Valuation Allowance [Roll Forward]
Valuation allowance, beginning of year	$ 143,818	$ 123,936	$ 121,524
Additions	29,359	27,591	13,933
Reversals	(13,631)	(7,709)	(11,521)
Valuation allowance, end of year	159,546	143,818	$ 123,936
Valuation Allowance, Deferred Tax Asset, Change in Amount	$ 15,700
Federal Net Operating Loss Deduction Limit, Percent	80.00%
Domestic Tax Authority [Member]
Reconciliation Of Valuation Allowance [Roll Forward]
Operating Loss Carryforwards	$ 10,300	11,700
State and Local Jurisdiction [Member]
Reconciliation Of Valuation Allowance [Roll Forward]
Operating Loss Carryforwards	$ 72,900	$ 20,300

Note 19. Income Taxes (Detail_3

Note 19. Income Taxes (Details) - Uncertainties - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning of year	$ 84,173	$ 89,256	$ 141,755
Increases related to prior year tax positions	0	3,827	0
Decreases related to prior year tax positions	(2,979)	0	(6,119)
Decreases from lapse in statute of limitations	(10,704)	(11,840)	(14,421)
Decreases relating to settlements with authorities	0	(2,494)	(35,416)
Increases related to current tax positions	1,703	5,424	3,457
Unrecognized tax benefits, end of year	72,193	84,173	$ 89,256
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	70,400
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	$ 5,300	5,500
Germany
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Tax Adjustments, Settlements, and Unusual Provisions		$ 2,500
Australia
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Open Tax Years	2013 - 2017
India
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Open Tax Years	2013 - 2018
Malaysia
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Open Tax Years	2013 - 2017
United States
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Open Tax Years	2008 - 2009; 2013 - 2017
Maximum [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	$ 100

Note 20. Net Income (Loss) Pe_3

Note 20. Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income (loss)	$ 144,326	$ (165,615)	$ (416,112)
Weighted-average common shares outstanding	104,745	104,328	102,866
Effect of restricted and performance stock units and stock purchase plan shares	1,368	0	0
Weighted-average shares used in computing diluted net (loss) income per share	106,113	104,328	102,866
Net income (loss) per share, basic	$ 1.38	$ (1.59)	$ (4.05)
Net income (loss) per share, diluted	$ 1.36	$ (1.59)	$ (4.05)
Anti-dilutive shares	299	1,021	753

Note 21. Accumulated Other Co_3

Note 21. Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stockholders' equity, beginning balance	$ 5,098,697	$ 5,218,349	$ 5,618,396
Amounts reclassified from accumulated other comprehensive (loss) income	(48,593)	140	(44,825)
Net other comprehensive (loss) income	(56,725)	12,166	(25,387)
Stockholders' equity, ending balance	5,212,403	5,098,697	5,218,349
Other income, net	39,737	23,965	40,252
Net sales	2,244,044	2,941,324	2,904,563
Cost of sales	1,851,867	2,392,377	2,266,145
Foreign currency loss, net	(570)	(9,640)	(14,007)
Interest expense, net	25,921	25,765	20,538
Income (loss) before taxes and equity in earnings	113,147	202,115	(537,251)
Total amount reclassified	48,593	(140)	44,825
Foreign Currency Translation Adjustment [Member]
Stockholders' equity, beginning balance	(65,346)
Other comprehensive loss before reclassifications	(1,034)
Amounts reclassified from accumulated other comprehensive (loss) income	0
Net tax effect	0
Net other comprehensive (loss) income	(1,034)
Stockholders' equity, ending balance	(66,380)	(65,346)
Total amount reclassified	0
Unrealized Gain (Loss) on Marketable Securities and Restricted Investments [Member]
Stockholders' equity, beginning balance	68,388
Other comprehensive loss before reclassifications	(6,077)
Amounts reclassified from accumulated other comprehensive (loss) income	(55,405)
Net tax effect	3,735
Net other comprehensive (loss) income	(57,747)
Stockholders' equity, ending balance	10,641	68,388
Total amount reclassified	55,405
Unrealized Gain (Loss) on Marketable Securities and Restricted Investments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Other income, net	55,405	49	41,633
Unrealized Gain (Loss) on Derivative Instruments [Member]
Stockholders' equity, beginning balance	(783)
Other comprehensive loss before reclassifications	(3,760)
Amounts reclassified from accumulated other comprehensive (loss) income	6,812
Net tax effect	(996)
Net other comprehensive (loss) income	2,056
Stockholders' equity, ending balance	1,273	(783)
Total amount reclassified	(6,812)
Unrealized Gain (Loss) on Derivative Instruments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Income (loss) before taxes and equity in earnings	(6,812)	(189)	3,192
Unrealized Gain (Loss) on Derivative Instruments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Foreign exchange forward contracts [Member]
Other income, net	546	(189)	0
Net sales	(1,698)	0	0
Cost of sales	(212)	0	0
Foreign currency loss, net	(5,448)	0	0
Unrealized Gain (Loss) on Derivative Instruments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Cross-currency swap contract
Foreign currency loss, net	0	0	4,896
Unrealized Gain (Loss) on Derivative Instruments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Foreign exhange forward, interest rate, and cross currency swap contracts [Member]
Interest expense, net	0	0	(1,704)
Total, Accumulated Other Comprehensive (Loss) Income [Member]
Stockholders' equity, beginning balance	2,259	(9,907)	15,480
Other comprehensive loss before reclassifications	(10,871)
Amounts reclassified from accumulated other comprehensive (loss) income	(48,593)
Net tax effect	2,739
Net other comprehensive (loss) income	(56,725)	12,166	(25,387)
Stockholders' equity, ending balance	(54,466)	$ 2,259	$ (9,907)
Total amount reclassified	$ 48,593

Note 22. Segment and Geograph_3

Note 22. Segment and Geographical Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)segments	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segments	2
Net sales	$ 2,244,044	$ 2,941,324	$ 2,904,563
Gross (loss) profit	392,177	548,947	638,418
Depreciation and amortization expense	104,444	91,899	204,251
Goodwill	14,462	14,462	14,462
Modules segment [Member]
Segment Reporting Information [Line Items]
Net sales	502,001	806,398	675,452
Gross (loss) profit	(50,467)	112,338	110,510
Depreciation and amortization expense	85,797	67,597	186,736
Goodwill	14,462	14,462
Systems segment [Member]
Segment Reporting Information [Line Items]
Net sales	1,742,043	2,134,926	2,229,111
Gross (loss) profit	442,644	436,609	527,908
Depreciation and amortization expense	18,647	24,302	$ 17,515
Goodwill	$ 0	$ 0

Note 22. Segment and Geograph_4

Note 22. Segment and Geographical Information (Details) - Revenues and Long-Lived Assets by Geographic Region - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 2,244,044	$ 2,941,324	$ 2,904,563
Long-lived assets	2,563,280	2,074,362
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	1,478,034	2,273,774	2,418,974
Long-lived assets	659,854	595,062
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	234,814	4,405	5,183
Long-lived assets	319,571	251,559
India
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	232,130	141,491	158,182
Australia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	153,163	108,643	9,568
Turkey
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	19,354	124,433	18,809
Jordan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	2,150	2,255	103,022
Spain
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	741	379	141,319
Vietnam
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	702,071	252,417
Malaysia
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	532,418	483,884
Chile
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	240,495	251,208
All other foreign countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	123,658	285,944	$ 49,506
Long-lived assets	$ 108,871	$ 240,232

Note 23. Concentrations of Ri_3

Note 23. Concentrations of Risks (Details) - Customer Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Maximum [Member]
Concentration Risk [Line Items]
Concentration risk, percentage threshold	10.00%
Net sales [Member] | Customer One [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	16.00%
Net sales [Member] | Customer Two [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	13.00%	47.00%
Net sales [Member] | Customer Seven [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			39.00%
Net sales [Member] | Customer Eight [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			11.00%
Net sales [Member] | Customer Nine [Domain]
Concentration Risk [Line Items]
Concentration risk, percentage			10.00%
Accounts receivable [Member] | Customer Three [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	18.00%
Accounts receivable [Member] | Customer Four [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%
Accounts receivable [Member] | Customer Five [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		26.00%
Accounts receivable [Member] | Customer Six [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		12.00%
Accounts receivable [Member] | Customer Ten [Domain]
Concentration Risk [Line Items]
Concentration risk, percentage			32.00%
Accounts receivable [Member] | Customer Eleven [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			12.00%