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Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 30, 2017 | Dec. 31, 2016 | Jan. 02, 2016
Commitments And Contingencies [Line Items] |  |  |
Total rent expense | $ 10,931 | $ 10,153 | $ 10,503
Unconditional purchase obligations due in one year | $ 10,725 |  |
Minimum employee age to partake in 401(k) | 18 years |  |
Requisite service period to partake in 401(k) | 1 month |  |
Employers' percentage match of employee's contribution percentage | 100.00% |  |
Percentage of employee's gross pay that is matched by the employer | 1.00% |  |
Employers' percentage match of employee's contribution percentage over one percent | 50.00% |  |
Employers' maximum contribution of employee's compensation | 6.00% |  |
Requisite service in order to cliff vest | 2 years |  |
Contributions made by the Company | $ 1,794 | $ 1,594 | $ 1,458
Buildings [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Lease expiration date | 2026 |  |
Equipment [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Lease expiration date | 2021 |  |

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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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- Definition Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308 + Details
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