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Benefit Plans - The Company's Pension Plan Assets Measured at Fair Value (Details) - USD ($) $ in Thousands | Dec. 28, 2019 | Dec. 29, 2018
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | $ 78,502 | $ 70,676
Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 20,935 | 20,888
Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 56,246 | 46,470
Insurance contracts and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 756 | 1,793
Cash and cash equivalents, and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 565 | 1,525
Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 6,718 | 5,399
Level 1 | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 1,796 | 1,361
Level 1 | Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 4,535 | 3,336
Level 1 | Insurance contracts and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 1 | Cash and cash equivalents, and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 387 | 702
Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 2 | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 2 | Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 2 | Insurance contracts and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 2 | Cash and cash equivalents, and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 609 | 632
Level 3 | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 3 | Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
Level 3 | Insurance contracts and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 609 | 632
Level 3 | Cash and cash equivalents, and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 0 | 0
NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 71,175 | 64,645
NAV | Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 19,139 | 19,527
NAV | Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 51,711 | 43,134
NAV | Insurance contracts and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | 147 | 1,161
NAV | Cash and cash equivalents, and other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total pension plan assets | $ 178 | $ 823

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