Segment and Geographical Information - Narrative (Details)	12 Months Ended
Dec. 29, 2019	Dec. 30, 2018
Segment Reporting [Abstract]
Equity method investee, percentage ownership sold		0.49
Ownership retained after deconsolidation	0.51

Subsidiary or Equity Method Investee, Percentage Ownership Retained After Deconsolidation

No definition available.

Name:	spwr_SubsidiaryorEquityMethodInvesteePercentageOwnershipRetainedAfterDeconsolidation
Namespace Prefix:	spwr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration