Stock Based Compensation (Narrative) (Details) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 27, 2019 USD ($) $ / shares shares
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted \| shares	430,412
Weighted average grant-date fair value \| $ / shares	$ 18.45
Shares outstanding \| shares	948,144
Nonvested weighted average grant-date fair value \| $ / shares	$ 17.44
Compensation expense \| $	$ 10.5
Weighted average period	2 years 3 months 18 days
Common Stock Subject to Vesting Requirements [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted \| shares	30,773
Weighted average grant-date fair value \| $ / shares	$ 15.57
Shares outstanding \| shares	96,639
Nonvested weighted average grant-date fair value \| $ / shares	$ 19.46
Compensation expense \| $	$ 1.8
Weighted average period	1 year 7 months 6 days

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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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