Value Creation Plan (Disclosure of costs incurred and charged to expense in Value Creation Plan) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Restructuring Cost and Reserve [Line Items]
Selling, general and administrative expenses	$ 29,278	$ 27,674	$ 84,783	$ 81,184
Value Creation Plan [Member]
Restructuring Cost and Reserve [Line Items]
Selling, general and administrative expenses	935	1,615	2,434	2,772
Other expense	54	3,222	1,029	5,598
Restructuring charges	$ 989	$ 4,837	$ 3,463	$ 8,370

Amount of expense classified as other.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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