Profit Sharing and 401(k) Plan (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Defined Contribution Plan Disclosure [Line Items]
Employee compensation deferral (in hundredths)			50.00%
Employer Contributions	$ 1.5	$ 1.4	$ 4.2	$ 3.9

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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