Profit Sharing and 401(k) Plan (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Defined Contribution Plan Disclosure [Line Items]
Employee compensation deferral (in hundredths)			50.00%
Employer Contributions	$ 1.4	$ 1.1	$ 3.9	$ 3.4

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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