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Associate Retirement Plans - Summary of Fair Value Pension Plan Asset (Detail) - USD ($) $ in Thousands | Dec. 30, 2017 | Dec. 31, 2016 | Jan. 02, 2016
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | $ 81,255 | $ 81,982 |
Total net asset value | 66,327 | 64,684 |
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 1,037 | 1,872 |
Significant unobservable inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 13,891 | 15,426 |
Mutual funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 18,194 | 14,178 |
Total net asset value | 18,194 | 14,178 |
Pooled funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 48,133 | 50,506 |
Total net asset value | 48,133 | 50,506 |
Money market fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 1,037 | 1,872 |
Money market fund [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 1,037 | 1,872 |
Guaranteed annuity contract [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 13,891 | 15,426 |
Guaranteed annuity contract [Member] | Significant unobservable inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | $ 13,891 | $ 15,426 | $ 16,198

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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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