Segment and Geographical Information (Details)			3 Months Ended								9 Months Ended		12 Months Ended
	Nov. 05, 2018 USD ($)	Aug. 09, 2018 USD ($)	Dec. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jul. 01, 2018 USD ($)	Apr. 01, 2018 USD ($)	Dec. 31, 2017 USD ($)	Oct. 01, 2017 USD ($)	Jul. 02, 2017 USD ($)	Apr. 02, 2017 USD ($)	Sep. 30, 2018 USD ($) segments	Oct. 02, 2016 segments	Dec. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of business segments | segments											3	3
Ownership percentage in equity method investment		7.70%
Revenue			$ 456,837,000	$ 428,263,000	$ 449,097,000	$ 391,888,000	$ 651,134,000	$ 485,836,000	$ 327,981,000	$ 329,095,000			$ 1,726,085,000	$ 1,794,047,000	$ 2,552,637,000
Gross profit/margin			(7,571,000)	$ 9,755,000	$ (310,215,000)	$ 10,248,000	(13,593,000)	$ 21,289,000	$ 16,167,000	$ (45,584,000)			(297,081,000)	(18,645,000)	221,819,000
Loss before income taxes and equity in earnings of unconsolidated investees													(898,671,000)	(1,200,750,000)	(528,392,000)
Impairment of residential lease assets											$ (14,800,000)
Stock-based compensation													(26,353,000)	(34,674,000)	(61,498,000)
Amortization of intangible assets													(9,600,000)	(19,700,000)	(13,000,000)
Non-cash interest expense													(15,346,000)	(18,390,000)	(1,057,000)
Gain on business divestitures		$ 59,347,000
Restructuring expense													(17,497,000)	(21,045,000)	(207,190,000)
Goodwill impairment													0	0	(147,365,000)
Equity in earnings of unconsolidated investees													(17,815,000)	25,938,000	14,295,000
Net loss attributable to noncontrolling interests and redeemable noncontrolling interests													106,405,000	241,747,000	72,780,000
Property, plant and equipment, net			839,871,000				1,147,845,000						839,871,000	1,147,845,000
Impairment of residential lease assets													251,984,000	624,335,000	(7,263,000)
SunPower Energy Services
Segment Reporting Information [Line Items]
Revenue													1,045,614,000	910,206,000	999,000,000
Property, plant and equipment, net			512,953,000				445,241,000						512,953,000	445,241,000
SunPower Technologies
Segment Reporting Information [Line Items]
Revenue													680,471,000	883,841,000	1,553,637,000
Property, plant and equipment, net			323,941,000				698,553,000						323,941,000	698,553,000
Corporate
Segment Reporting Information [Line Items]
Property, plant and equipment, net			2,977,000				4,051,000						2,977,000	4,051,000
Operating Segments
Segment Reporting Information [Line Items]
Total segment revenue as reviewed by CODM													2,203,473,000	2,595,507,000	3,149,397,000
Gross profit/margin													161,137,000	261,623,000	410,816,000
Loss before income taxes and equity in earnings of unconsolidated investees													179,075,000	255,559,000	384,924,000
Operating Segments | SunPower Energy Services
Segment Reporting Information [Line Items]
Total segment revenue as reviewed by CODM													1,143,967,000	1,170,253,000	1,091,548,000
Gross profit/margin													142,087,000	126,049,000	209,075,000
Loss before income taxes and equity in earnings of unconsolidated investees													151,095,000	109,863,000	141,885,000
Operating Segments | SunPower Energy Services | North America Residential
Segment Reporting Information [Line Items]
Revenue													673,758,000	531,291,000	639,174,000
Operating Segments | SunPower Energy Services | North America Commercial
Segment Reporting Information [Line Items]
Revenue													422,762,000	596,729,000	415,247,000
Operating Segments | SunPower Energy Services | Operations and maintenance
Segment Reporting Information [Line Items]
Revenue													47,447,000	42,233,000	37,127,000
Operating Segments | SunPower Energy Services | International DG
Segment Reporting Information [Line Items]
Revenue													0	0	0
Operating Segments | SunPower Energy Services | Module sales
Segment Reporting Information [Line Items]
Revenue													0	0	0
Operating Segments | SunPower Energy Services | Development Services And Legacy Power Plant
Segment Reporting Information [Line Items]
Revenue													0	0	0
Operating Segments | SunPower Technologies
Segment Reporting Information [Line Items]
Total segment revenue as reviewed by CODM													1,059,506,000	1,425,254,000	2,057,849,000
Gross profit/margin													19,050,000	135,574,000	201,741,000
Loss before income taxes and equity in earnings of unconsolidated investees													27,980,000	145,696,000	243,039,000
Operating Segments | SunPower Technologies | North America Residential
Segment Reporting Information [Line Items]
Revenue													0	0	0
Operating Segments | SunPower Technologies | North America Commercial
Segment Reporting Information [Line Items]
Revenue													0	0	0
Operating Segments | SunPower Technologies | Operations and maintenance
Segment Reporting Information [Line Items]
Revenue													0	0	0
Operating Segments | SunPower Technologies | International DG
Segment Reporting Information [Line Items]
Revenue													322,028,000	209,346,000	153,894,000
Operating Segments | SunPower Technologies | Module sales
Segment Reporting Information [Line Items]
Revenue													186,712,000	173,617,000	107,412,000
Operating Segments | SunPower Technologies | Development Services And Legacy Power Plant
Segment Reporting Information [Line Items]
Revenue													162,227,000	575,342,000	1,350,006,000
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue													(388,539,000)	(466,949,000)	(446,537,000)
Gross profit/margin													(25,386,000)	(25,151,000)	(18,045,000)
Intersegment Eliminations | SunPower Energy Services
Segment Reporting Information [Line Items]
Revenue													0	0	0
Intersegment Eliminations | SunPower Technologies
Segment Reporting Information [Line Items]
Revenue													388,539,000	466,949,000	446,537,000
Segment Reconciling Items
Segment Reporting Information [Line Items]
8point3													(8,588,000)	7,198,000	29,614,000
Utility and power plant projects													4,145,000	(54,659,000)	(13,981,000)
Sale of operating lease assets													0	0	(28,096,000)
Sale-leaseback transactions													101,582,000	272,654,000	78,532,000
Gross profit/margin | Segment Reconciling Items
Segment Reporting Information [Line Items]
8point3													8,337,000	2,656,000	23,157,000
Utility and power plant projects													1,244,000	(41,746,000)	(6,064,000)
Sale of operating lease assets													0	0	(8,554,000)
Sale-leaseback transactions													(242,000)	(31,094,000)	(11,352,000)
Impairment of property, plant and equipment													(355,107,000)	0	0
Impairment of residential lease assets													14,847,000	0	0
Arbitration ruling													0	0	5,852,000
Cost of above-market polysilicon													(87,228,000)	(166,906,000)	(148,265,000)
Stock-based compensation													(4,996,000)	(5,489,000)	(17,090,000)
Amortization of intangible assets													(8,966,000)	(10,206,000)	(7,680,000)
Depreciation of idle equipment													(721,000)	(2,300,000)	0
Non-cash interest expense													0	(32,000)	(956,000)
Loss before taxes and equity in earnings of unconsolidated investees | Segment Reconciling Items
Segment Reporting Information [Line Items]
8point3													(8,485,000)	78,990,000	25,127,000
Utility and power plant projects													1,244,000	(41,746,000)	(6,602,000)
Sale of operating lease assets													0	0	(8,607,000)
Sale-leaseback transactions													18,802,000	39,318,000	11,699,000
Impairment of property, plant and equipment													369,168,000	0	0
Impairment of residential lease assets													227,507,000	473,709,000	0
Arbitration ruling													0	0	5,852,000
IPO-related costs													0	(82,000)	(304,000)
Cost of above-market polysilicon													87,228,000	166,906,000	148,265,000
Stock-based compensation													28,215,000	34,674,000	61,498,000
Amortization of intangible assets													8,966,000	19,048,000	17,369,000
Depreciation of idle equipment													721,000	2,300,000	0
Non-cash interest expense													68,000	128,000	1,057,000
Other													0	0	(31,000)
Acquisition-related and other costs													17,727,000	0	0
Gain on business divestitures													59,347,000	0	0
Restructuring expense													17,497,000	21,045,000	207,189,000
Goodwill impairment													0	0	57,765,000
Unrealized loss on equity investments													(6,375,000)	0	0
Equity in earnings of unconsolidated investees													17,815,000	(25,938,000)	(14,295,000)
Net loss attributable to noncontrolling interests and redeemable noncontrolling interests													106,406,000	241,747,000	72,780,000
Cash interest expense, net of interest income													86,394,000	79,965,000	57,734,000
Depreciation													120,367,000	164,970,000	156,464,000
Business reorganization costs													1,330,000	0	0
Loss before taxes and equity in earnings of unconsolidated investees | Corporate
Segment Reporting Information [Line Items]
Loss before income taxes and equity in earnings of unconsolidated investees													(67,866,000)	(65,907,000)	$ (73,052,000)
United States
Segment Reporting Information [Line Items]
Property, plant and equipment, net			$ 575,451,000				$ 488,970,000						$ 575,451,000	$ 488,970,000
SunStrong
Segment Reporting Information [Line Items]
Ownership percentage in equity method investment	51.00%
Disposal Group, Disposed of by Sale, Not Discontinued Operations | SunStrong Residential Lease Portfolio, Portion Of Interest
Segment Reporting Information [Line Items]
Disposal consideration	$ 10,000,000
Ownership interest sold	49.00%
Sales Revenue, Net | Customer Concentration Risk | Power Plant | Actis GP LLP
Segment Reporting Information [Line Items]
Concentration risk, percentage														13.00%
Sales Revenue, Net | Customer Concentration Risk | Power Plant | 8point3
Segment Reporting Information [Line Items]
Concentration risk, percentage															10.00%
Sales Revenue, Net | Customer Concentration Risk | Power Plant | Southern Renewable Partnerships
Segment Reporting Information [Line Items]
Concentration risk, percentage															15.00%
Sales Revenue, Net | Geographic Concentration Risk | United States
Segment Reporting Information [Line Items]
Concentration risk, percentage													68.00%	79.00%	85.00%
Sales Revenue, Net | Geographic Concentration Risk | Japan
Segment Reporting Information [Line Items]
Concentration risk, percentage													5.00%	6.00%	6.00%
Sales Revenue, Net | Geographic Concentration Risk | Rest of World
Segment Reporting Information [Line Items]
Concentration risk, percentage													27.00%	15.00%	9.00%
Sales Revenue, Net | Geographic Concentration Risk | All Countries
Segment Reporting Information [Line Items]
Concentration risk, percentage													100.00%	100.00%	100.00%