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Associate Retirement Plans - Summary of Fair Value Pension Plan Asset (Detail) - USD ($) $ in Thousands | Dec. 29, 2018 | Dec. 30, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | $ 74,241 | $ 81,255 |
Mutual funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 20,124 | 18,194 |
Pooled funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 29,576 | 48,133 |
Money market fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 11,992 | 1,037 |
Guaranteed annuity contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 12,549 | 13,891 | $ 15,426
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 11,992 | 1,037 |
Level 2 [Member] | Money market fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 11,992 | 1,037 |
Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 12,549 | 13,891 |
Level 3 [Member] | Guaranteed annuity contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 12,549 | 13,891 |
NAV |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 49,700 | 66,327 |
NAV | Mutual funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 20,124 | 18,194 |
NAV | Pooled funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | $ 29,576 | $ 48,133 |

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