Accounts Receivable, Unbilled and Retainage

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Contract Asset, Net Change

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Contract Asset, Percent Change

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Contract Liability, Net Change

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Contract Liability, Percent Change

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Increase (Decrease) in Revenue from Net Changes in Estimates

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Increase (Decrease) in Revenue from Net Changes in Indirect Tax Estimates

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Increase (Decrease) in Revenue from Net Changes in Input Cost Estimates

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Increase (Decrease) in Revenue from Net Changes in Transaction Price

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Net Change in Estimate as a Percentage of Aggregate Revenue for Associated Projects

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Number of projects affected

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Project Change in Estimate Disclosure Threshold

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Remaining Performance Obligations, Percent of Revenue Recognized

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[Line Items] for Revenue from Contracts with Customers [Table]

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Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract.

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- Definition

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

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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

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

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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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12. Revenue from Contracts with Customers (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) Projects	Sep. 30, 2017 USD ($) Projects	Sep. 30, 2018 USD ($) Projects	Sep. 30, 2017 USD ($) Projects	Dec. 31, 2017 USD ($)
Revenue from Contracts with Customers [Line Items]
Net sales	$ 676,220	$ 1,087,026	$ 1,552,803	$ 2,602,143
Project Change in Estimate Disclosure Threshold			$ 1,000
Number of Projects with Changes in Estimates \| Projects	2	2	23	4
Increase (Decrease) in Revenue from Net Changes in Transaction Prices	$ 6,672	$ 1,153	$ 54,653	$ (14)
(Decrease) Increase in Revenue from Net Changes in Input Cost Estimates	(2,948)	2,874	(13,070)	4,994
Net Increase in Revenue from Net Changes in Estimates	$ 3,724	$ 4,027	$ 41,583	$ 4,980
Net Change in Estimate as a Percentage of Aggregate Revenue for Associated Projects	0.30%	1.10%	0.40%	0.80%
Increase in Revenue from Net Changes in Indirect Tax Estimates			$ 54,600
Accounts receivable, unbilled	$ 410,513		410,513		$ 172,594
Retainage	10,621		10,621		2,014
Accounts receivable, unbilled and retainage	421,134		421,134		174,608
Contract Asset, Net Change			$ 246,526
Contract Asset, Percent Change			141.00%
Deferred Revenue	263,577		$ 263,577		145,073
Contract Liability, Net Change			$ 118,504
Contract Liability, Percent Change			82.00%
Deferred Revenue, Noncurrent	47,677		$ 47,677		$ 63,257
Sales Revenue Net, from Beginning Contract Liability			71,900	$ 308,600
Solar Modules [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	119,825	$ 300,297	386,450	599,827
Remaining Performance Obligation, Transaction Price	3,100,000		3,100,000
Solar Power Systems [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	386,237	747,579	850,306	1,840,097
EPC Services [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	134,369	272	203,941	40,706
O&M Services [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	25,431	25,414	76,572	75,074
Remaining Performance Obligation, Transaction Price	$ 500,000		$ 500,000
Revenue, Remaining Performance Obligation, Period of Recognition	11 years 6 months		11 years 6 months
Energy Generation [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	$ 10,358	13,461	$ 35,534	43,125
Module Plus [Member]
Revenue from Contracts with Customers [Line Items]
Net sales	0	$ 3	0	$ 3,314
Solar Power Systems, Sales of and EPC Services [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligation, Transaction Price	$ 1,100,000		$ 1,100,000
Solar Power Systems, Sales of and EPC Services [Member] \| California Flats [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	87.00%		87.00%
Solar Power Systems, Sales of and EPC Services [Member] \| Phoebe [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	2.00%		2.00%
Solar Power Systems, Sales of and EPC Services [Member] \| GA Solar 4 [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	6.00%		6.00%
Solar Power Systems, Sales of and EPC Services [Member] \| Rosamond [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	48.00%		48.00%
Solar Power Systems, Sales of and EPC Services [Member] \| Willow Springs [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	56.00%		56.00%
Solar Power Systems, Sales of and EPC Services [Member] \| Grange Hall [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	23.00%		23.00%
Solar Power Systems, Sales of and EPC Services [Member] \| Peace Creek [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	10.00%		10.00%
Solar Power Systems, Sales of and EPC Services [Member] \| Troy Solar [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	0.00%		0.00%
Solar Power Systems, Sales of and EPC Services [Member] \| Lake Hancock [Member]
Revenue from Contracts with Customers [Line Items]
Remaining Performance Obligations, Percent of Revenue Recognized	0.00%		0.00%