Carrying value of debt instrument.

No definition available.

Name:	spwr_DebtInstrumentsCarryingValue
Namespace Prefix:	spwr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Topic 835
-SubTopic 30
-Section 55
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+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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+ Details

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=spwr_OtherDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConvertibleDebtMember
Namespace Prefix:
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Period Type:

Debt and Credit Sources - Schedule of Debt (Details) - USD ($)	Mar. 29, 2020	Dec. 29, 2019	Dec. 31, 2015	Sep. 28, 2014	Jun. 30, 2014	Jun. 29, 2014	Dec. 31, 2010
Debt Instrument [Line Items]
Face Value	$ 959,353,000	$ 1,045,966,000
Short-term	124,060,000	104,230,000
Long-term	827,438,000	932,624,000
Total	$ 951,498,000	1,036,854,000
0.875% debentures due 2021
Debt Instrument [Line Items]
Face Value					$ 400,000,000.0
Interest rate	0.875%				0.875%
4.00% debentures due 2023
Debt Instrument [Line Items]
Face Value			$ 425,000,000.0
Interest rate	4.00%		4.00%
CEDA loan
Debt Instrument [Line Items]
Face Value	$ 30,000,000	30,000,000					$ 30,000,000.0
Short-term	0	0
Long-term	29,161,000	29,141,000
Total	29,161,000	29,141,000
Non-recourse financing and other debt
Debt Instrument [Line Items]
Face Value	194,655,000	190,966,000
Short-term	124,060,000	104,230,000
Long-term	67,640,000	83,224,000
Total	191,700,000	187,454,000
Convertible Debt
Debt Instrument [Line Items]
Face Value	734,698,000	825,000,000
Convertible Debt \| 0.875% debentures due 2021
Debt Instrument [Line Items]
Face Value	309,698,000	400,000,000		$ 400.0
Short-term	0	0
Long-term	309,126,000	399,058,000
Total	309,126,000	399,058,000
Interest rate						0.875%
Convertible Debt \| 4.00% debentures due 2023
Debt Instrument [Line Items]
Face Value	425,000,000	425,000,000	$ 425,000,000.0
Short-term	0	0
Long-term	421,511,000	421,201,000
Total	$ 421,511,000	$ 421,201,000