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Employee Benefits - Schedule of Fair Value of Total Assets By Category (Details) - USD ($) $ in Thousands | Dec. 29, 2018 | Dec. 30, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | $ 81,241 | $ 88,452 | $ 79,087
Pension Plan |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 81,268 | 88,452 |
Pension Plan | Level 1 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 853 | 32,803 |
Pension Plan | Level 2 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 80,415 | 55,649 |
Pension Plan | Level 3 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 0 | 0 |
Pension Plan | Return-seeking securities - Corporate bonds |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 0 | 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 | 0 | 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 | 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 | 0 |
Pension Plan | Global equity securities |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 0 | 25 |
Pension Plan | Global equity securities | Level 1 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 0 | 25 |
Pension Plan | Global equity securities | Level 2 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 0 | 0 |
Pension Plan | Global equity securities | Level 3 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 0 | 0 |
Pension Plan | Return-seeking securities - Collective investment trust |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 55,766 | 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 | 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 | 55,766 | 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 | 0 |
Pension Plan | Liability-matching securities - Corporate bonds |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 0 | 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 | 0 | 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 | 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 | 0 |
Pension Plan | Liability-matching securities - Collective investment trusts |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 24,649 | 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 | 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 | 24,649 | 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 | 0 |
Pension Plan | Cash and cash equivalents |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 853 | 1,674 |
Pension Plan | Cash and cash equivalents | Level 1 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | 853 | 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 | 0 |
Pension Plan | Cash and cash equivalents | Level 3 |  |  |
Asset allocation structure of the portfolio |  |  |
Fair value of plan assets by asset category | $ 0 | $ 0 |

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