10. Commitments and Contingencies (Details) - Product Warranties - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Movement in Standard Product Warranty Accrual [Roll Forward]
Product warranty liability, beginning of period	$ 217,241	$ 225,800	$ 220,692	$ 224,274
Accruals for new warranties issued	4,797	1,836	9,913	5,468
Settlements	(2,944)	(2,472)	(6,022)	(5,081)
Changes in estimate of product warranty liability	(1,103)	649	(6,592)	1,152
Product warranty liability, end of period	217,991	225,813	217,991	225,813
Current portion of warranty liability	41,930	32,241	41,930	32,241
Noncurrent portion of warranty liability	$ 176,061	$ 193,572	$ 176,061	$ 193,572
Percentage Point Change in Estimated Rate of Return of Module Warranty	1.00%		1.00%
Estimated Change in Module Warranty from Sensitivity Analysis	$ 79,500		$ 79,500
Percentage Point Change in Estimated Rate of Return of Balance of Systems Warranty	1.00%		1.00%
Minimum [Member]
Movement in Standard Product Warranty Accrual [Roll Forward]
Estimated Rate of Return for Module Warranty	1.00%		1.00%
Maximum [Member]
Movement in Standard Product Warranty Accrual [Roll Forward]
Estimated Rate of Return for Module Warranty	3.00%		3.00%

Estimated Change in Module Warranty from Sensitivity Analysis

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Estimated Rate of Return for Module Warranty

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Percentage Point Change in Estimated Rate of Return of Balance of Systems Warranty

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Percentage Point Change in Estimated Rate of Return of Module Warranty

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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Amount as of the balance sheet date of the aggregate standard product warranty liability that is expected to be paid within one year or the normal operating cycle, if longer. Does not include the balance for the extended product warranty liability.

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Amount as of the balance sheet date of the aggregate standard product warranty liability that is expected to be paid after one year or beyond the normal operating cycle, if longer. Does not include the balance for the extended product warranty liability.

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Amount of decrease in the standard product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard product warranty. Excludes extended product warranties.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of increase (decrease) in the standard product warranty accrual from changes in estimates attributable to preexisting product warranties. Excludes extended product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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