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Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2026	Sep. 27, 2025	Sep. 26, 2026	Sep. 27, 2025	Dec. 27, 2025
Related Party Transaction
Sales to related party	$ 766,729	$ 624,640	$ 2,162,479	$ 1,792,360
Accounts receivable balance	438,145		438,145		$ 363,215
Accounts payable balance	$ 260,080		$ 260,080		211,079
Related Party \| Powersem
Related Party Transaction
Ownership percentage (as a percent)	45.00%		45.00%
Related Party \| EB Tech
Related Party Transaction
Ownership percentage (as a percent)	15.00%		15.00%
Related Party \| ATEC
Related Party Transaction
Ownership percentage (as a percent)	24.00%		24.00%
Related Party \| Powersem
Related Party Transaction
Sales to related party	$ 500	300	$ 1,200	900
Purchase of material/service from related party	700	600	1,600	1,700
Accounts receivable balance	100		100		0
Accounts payable balance	100		100		100
Related Party \| EB Tech
Related Party Transaction
Sales to related party	0	0	0	0
Purchase of material/service from related party	100	100	300	800
Accounts receivable balance	0		0		0
Accounts payable balance	100		100		100
Related Party \| ATEC
Related Party Transaction
Sales to related party	0	0	0	0
Purchase of material/service from related party	2,300	$ 2,400	7,300	$ 5,700
Accounts receivable balance	0		0		0
Accounts payable balance	$ 800		$ 800		$ 2,100