Balance Sheet Components - Property, Plant and Equipment, Net (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 01, 2023	Oct. 02, 2022	Oct. 01, 2023	Oct. 02, 2022	Jan. 01, 2023
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 179,133,000		$ 179,133,000		$ 144,579,000
Vehicle finance leases	26,221,000		26,221,000		12,316,000
Less: accumulated depreciation and impairment	(73,064,000)		(73,064,000)		(68,106,000)
Property, plant and equipment, net	106,069,000		106,069,000		76,473,000
Property, plant and equipment, retired			21,900,000		100,000
Gain (loss) on disposal			0		0
Testing equipment and tools
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,973,000		1,973,000		1,157,000
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	17,137,000		17,137,000		16,960,000
Solar power systems
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	12,709,000		12,709,000		10,271,000
Computer equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	15,015,000		15,015,000		14,411,000
Internal-use software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	82,515,000		82,515,000		71,477,000
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	7,895,000		7,895,000		8,088,000
Transportation equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	6,481,000		6,481,000		3,941,000
Work-in-progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	9,187,000		9,187,000		$ 5,958,000
Asset Retirement Obligations
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$ 11,400,000	$ 6,000,000	$ 30,500,000	$ 14,000,000