Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 02, 2021	Oct. 03, 2020	Oct. 02, 2021	Oct. 03, 2020
Stock-based compensation costs
Stock based compensation costs	$ 14,296	$ 11,791	$ 36,916	$ 36,252
Income tax (expense) benefit	(627)	900	632	3,022
Share based compensation costs after tax	14,923	10,891	36,284	33,230
Total unrecognized compensation costs related to awards	90,100		$ 90,100
Weighted-average period of recognition of unrecognized compensation costs			2 years 3 months 18 days
Cost of revenues
Stock-based compensation costs
Stock based compensation costs	261	262	$ 696	717
Research and development
Stock-based compensation costs
Stock based compensation costs	7,071	5,821	18,190	17,354
Selling, general and administrative
Stock-based compensation costs
Stock based compensation costs	$ 6,964	$ 5,708	$ 18,030	$ 18,181

Amount of expense (benefit) for award under share-based payment arrangement.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount, after tax, of expense for award under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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