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Employee Benefits - Fair Value Of Plan Assets by Asset Category and Asset Categories As a Percentage of Total Assets (Details) - USD ($) $ in Thousands | Dec. 30, 2017 | Dec. 31, 2016 | Jan. 02, 2016
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Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets by asset category | $ 88,452 | $ 79,087 | $ 78,264
Actual Allocation (as a percent) | 100.00% | 100.00% |
Global equity securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets by asset category |  | $ 48,134 |
Actual Allocation (as a percent) |  | 61.00% |
Fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets by asset category |  | $ 30,493 |
Actual Allocation (as a percent) |  | 38.00% |
Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets by asset category |  | $ 460 |
Actual Allocation (as a percent) |  | 1.00% |

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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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