Related Party Transactions (Details) - Equity Method Investee - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 26, 2021	Jun. 27, 2020	Jun. 26, 2021	Jun. 27, 2020	Dec. 26, 2020
Powersem
Related Party Transaction
Ownership percentage (percent)	45.00%		45.00%
Sales to related party	$ 0.0	$ 0.3	$ 0.2	$ 0.7
Purchase material/service from related party	0.7	0.8	1.8	1.0
Accounts receivable balance	0.0		0.0		$ 0.1
Accounts payable balance	$ 0.1		$ 0.1		0.1
EB Tech
Related Party Transaction
Ownership percentage (percent)	19.00%		19.00%
Sales to related party	$ 0.0	0.0	$ 0.0	0.0
Purchase material/service from related party	0.1	0.0	0.2	0.0
Accounts receivable balance	0.0		0.0		0.0
Accounts payable balance	$ 0.0		$ 0.0		0.0
ATEC
Related Party Transaction
Ownership percentage (percent)	24.00%		24.00%
Sales to related party	$ 0.0	0.0	$ 0.0	0.0
Purchase material/service from related party	2.8	$ 1.6	5.8	$ 3.4
Accounts receivable balance	0.0		0.0		0.0
Accounts payable balance	$ 1.8		$ 1.8		$ 0.2

Amount for accounts payable to related parties.

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