Summary of Significant Accounting Policies Retirement Benefits (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 29, 2018 |
Dec. 30, 2017 |
Dec. 31, 2016 |
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| Retirement Benefits [Abstract] | |||
| Maximum Employee Contribution To Defined Contributions Plan | 8.00% | ||
| Defined Contribution Plan, Employer Matching Contribution, Percent of Match | 100.00% | ||
| Maximum Percentage Of Matching Contributions Made By Employer | 50.00% | ||
| Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay | 6.00% | ||
| Defined contribution plan costs | $ 2,567 | $ 2,222 | $ 2,101 |
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- Definition Maximum Employee Contribution To Defined Contributions Plan No definition available.
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- Definition Maximum Percentage Of Matching Contributions Made By Employer No definition available.
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- References No definition available.
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- Definition Amount of cost for defined contribution plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. No definition available.
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- Definition Percentage employer matches of the employee's percentage contribution matched. No definition available.
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