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Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2025	Sep. 28, 2024	Sep. 27, 2025	Sep. 28, 2024	Dec. 28, 2024
Related Party Transaction
Sales to related party	$ 624,640	$ 567,390	$ 1,792,360	$ 1,661,263
Accounts receivable balance	373,827		373,827		$ 294,371
Accounts payable balance	204,016		204,016		188,359
Related Party \| Powersem
Related Party Transaction
Sales to related party	300	300
Purchase material/service from related party	600	600
Accounts receivable balance	100		100		0
Accounts payable balance	300		300		700
Related Party \| EB Tech
Related Party Transaction
Sales to related party	0	0
Purchase material/service from related party	100	200
Accounts receivable balance	0		0		0
Accounts payable balance	0		0		100
Related Party \| ATEC
Related Party Transaction
Sales to related party	0	0
Purchase material/service from related party	2,400	$ 600
Accounts receivable balance	0		0		0
Accounts payable balance	$ 900		$ 900		$ 700
Powersem \| Related Party
Related Party Transaction
Ownership percentage (as a percent)	45.00%		45.00%
Sales to related party			$ 900	1,200
Purchase material/service from related party			$ 1,700	3,000
EB Tech \| Related Party
Related Party Transaction
Ownership percentage (as a percent)	15.00%		15.00%
Sales to related party			$ 0	0
Purchase material/service from related party			$ 800	600
ATEC \| Related Party
Related Party Transaction
Ownership percentage (as a percent)	24.00%		24.00%
Sales to related party			$ 0	0
Purchase material/service from related party			$ 5,700	$ 3,500