Related Party Transactions (Details) - Equity Method Investee - USD ($) $ in Millions	3 Months Ended
Mar. 27, 2021	Mar. 28, 2020	Dec. 26, 2020
Powersem
Related Party Transaction
Ownership percentage (percent)	45.00%
Sales to related party	$ 0.2	$ 0.4
Purchase material/service from related party	1.1	0.2
Accounts Receivable balance	0.0		$ 0.1
Accounts Payable balance	$ 0.2		0.1
EB Tech
Related Party Transaction
Ownership percentage (percent)	19.00%
Sales to related party	$ 0.0	0.0
Purchase material/service from related party	0.1	0.0
Accounts Receivable balance	0.0		0.0
Accounts Payable balance	$ 0.0		0.0
ATEC
Related Party Transaction
Ownership percentage (percent)	24.00%
Sales to related party	$ 0.0	0.0
Purchase material/service from related party	3.0	$ 1.8
Accounts Receivable balance	0.0		0.0
Accounts Payable balance	0.3		0.2
VTOOL Ltd. and Securepush Ltd.
Related Party Transaction
Cost method investments	$ 0.5		$ 0.5

Amount for accounts payable to related parties.

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