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Employee Benefits - Schedule of Fair Value of Total Assets By Category (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	$ 88,452	$ 79,087	$ 78,264
Global equity securities
Asset allocation structure of the portfolio
Fair value of plan assets by asset category		$ 48,134
Pension Plan
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	88,452
Pension Plan | Level 1
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	32,803
Pension Plan | Level 2
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	55,649
Pension Plan | Level 3
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Return-seeking securities - Corporate bonds
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	10,393
Pension Plan | Return-seeking securities - Corporate bonds | Level 1
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	10,393
Pension Plan | Return-seeking securities - Corporate bonds | Level 2
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Return-seeking securities - Corporate bonds | Level 3
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Global equity securities
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	25
Pension Plan | Global equity securities | Level 1
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	25
Pension Plan | Global equity securities | Level 2
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Global equity securities | Level 3
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Return-seeking securities - Collective investment trust
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	43,910
Pension Plan | Return-seeking securities - Collective investment trust | Level 1
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Return-seeking securities - Collective investment trust | Level 2
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	43,910
Pension Plan | Return-seeking securities - Collective investment trust | Level 3
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Liability-matching securities - Corporate bonds
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	20,711
Pension Plan | Liability-matching securities - Corporate bonds | Level 1
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	20,711
Pension Plan | Liability-matching securities - Corporate bonds | Level 2
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Liability-matching securities - Corporate bonds | Level 3
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Liability-matching securities - Collective investment trusts
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	11,739
Pension Plan | Liability-matching securities - Collective investment trusts | Level 1
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Liability-matching securities - Collective investment trusts | Level 2
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	11,739
Pension Plan | Liability-matching securities - Collective investment trusts | Level 3
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Cash and cash equivalents
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	1,674
Pension Plan | Cash and cash equivalents | Level 1
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	1,674
Pension Plan | Cash and cash equivalents | Level 2
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	0
Pension Plan | Cash and cash equivalents | Level 3
Asset allocation structure of the portfolio
Fair value of plan assets by asset category	$ 0

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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

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