Business Combinations Fair Value of Net assets acquired (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 01, 2017	Sep. 29, 2019
Fair value of net assets acquired [Abstract]
Business Combination, Prepaid assets acquired, Cell Supply Agreement		$ 16,928
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		22,875
Business Combination, Acquired Receivable, Fair Value		23,956
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		2,711
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		285,589
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		5,997
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets		342
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		367,470
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable		41,186
Business Combination, Accrued liabilities, Polysilicon supply agreement assumed		87,198
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Related Party Accounts Payable		14,333
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Employee related liabilities		4,017
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other		760
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt		58,248
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities		296
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		206,038
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		161,432
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory		$ 9,072
Goodwill, Acquired During Period	$ 89,600
Business Combination, Consideration Transferred	$ 251,032

Business Combination, Accrued liabilities, Polysilicon supply agreement assumed

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- Definition

Business Combination, Prepaid assets acquired, Cell Supply Agreement

+ References

No definition available.

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Related Party Accounts Payable

+ References

No definition available.

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Employee related liabilities

+ References

No definition available.

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- Definition

Fair value of net assets acquired [Abstract]

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No definition available.

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- Definition

Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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- Definition

Amount of assets acquired at the acquisition date.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

+ References

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of long-term debt due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

The amount of inventory recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

Amount of liabilities assumed at the acquisition date.

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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-Publisher FASB
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