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Associate Retirement Plans - Summary of Reconciliation of Beginning and Ending Balances for Level 3 Assets (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 | Jan. 02, 2016
Defined Benefit Plan Disclosure [Line Items] |  |
Balance at beginning of year | $ 84,753 |
Balance at end of year | 81,982 | $ 84,753
Guaranteed annuity contract [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Balance at beginning of year | 16,198 |
Balance at end of year | 15,426 | 16,198
Significant unobservable inputs (Level 3) [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Balance at beginning of year | 16,198 |
Balance at end of year | 15,426 | 16,198
Significant unobservable inputs (Level 3) [Member] | Guaranteed annuity contract [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Balance at beginning of year | 16,198 | 17,749
Purchases, sales, issuances and settlements, net | (1,733) | (2,227)
Interest income | 631 | 680
Unrealized gains (losses) | 330 | (4)
Balance at end of year | $ 15,426 | $ 16,198

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- Definition Defined benefit pensions plans interest income. + References No definition available. + Details
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- Definition Actual return on plan assets, separately identifying the amount related to assets sold during the period. + 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 (d)(iv)(02)(A) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(iv)(02)(A) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 + Details
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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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- Definition Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations. + 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 (d)(iv)(02)(B) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(iv)(02)(B) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 + Details
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