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Associate Retirement Plans - Summary of Fair Value Pension Plan Asset (Detail) - USD ($) $ in Thousands | Dec. 31, 2016 | Jan. 02, 2016 | Jan. 03, 2015
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | $ 81,982 | $ 84,753 |
Total net asset value | 64,684 | 67,756 |
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 1,872 | 799 |
Significant unobservable inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 15,426 | 16,198 |
Mutual funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 14,178 | 9,401 |
Total net asset value | 14,178 | 9,401 |
Pooled funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 50,506 | 58,355 |
Total net asset value | 50,506 | 58,355 |
Money market fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 1,872 | 799 |
Money market fund [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 1,872 | 799 |
Guaranteed annuity contract [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | 15,426 | 16,198 |
Guaranteed annuity contract [Member] | Significant unobservable inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total fair value | $ 15,426 | $ 16,198 | $ 17,749

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930 Reference 2: 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=58740216&loc=d3e1928-114920 + Details
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