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Associate Retirement Plans - Additional Information (Detail) | 12 Months Ended
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Dec. 30, 2017 USD ($) Trust | Dec. 31, 2016 USD ($) | Jan. 02, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined contribution plans expense | $ 7,900,000 | $ 11,900,000 | $ 21,100,000
Cash surrender value of plan assets included in other long term assets | 138,193,000 | 94,242,000 |
Aggregate amount of life insurance coverage | $ 15,000,000 |  |
Number of Trusts | Trust | 2 |  |
Percentage of trust funded with pre-merger liability to plan participants | 125.00% |  |
Proceeds from company owned life insurance |  |  | 5,004,000
Distribution charges | $ 2,600,000 | 2,800,000 |
Settlement accounting charges | $ 500,000 | 700,000 |
Defined contribution plan employees minimum period of service | 10 years |  |
Defined contribution plan employees age to eligible under the plan | 55 years |  |
Maximum age of major medical insurance with deductible and coinsurance provisions | 65 years |  |
Multiplier effect of Monthly postretirement health care benefits to covered employees | $ 5 |  |
Actuarial gains and losses are amortized when accumulation of such gains and losses exceeds | 10.00% |  |
Percentage point increase or decrease in assumed health care cost trend rate | 1.00% |  |
Critical and declining zone fund status | Less than 65 percent |  |
Michigan Conference of Teamsters and Ohio Conference of Teamsters Health and Welfare Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension contributions during last plan year | $ 14,100,000 | 14,300,000 | 15,100,000
Central States, Southeast and Southwest Areas Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension contributions during last plan year | $ 13,400,000 | 13,400,000 | $ 12,900,000
Collective bargaining arrangement description | The Company is party to four CBAs that require contributions to the Plan with expiration dates ranging from January 2019 to February 2021. These CBAs cover warehouse personnel and drivers in Grand Rapids, Michigan and Bellefontaine and Lima, Ohio. |  |
Cash Balance Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Average long-term expected return on pension plan assets | 4.84% |  |
Expected Company contribution in 2018 | $ 2,000,000 |  |
Retiree Medical Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected Company contribution in 2018 | 400,000 |  |
Maximum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
1% increase or decrease in assumed health care cost trend rate in accumulated postretirement benefit obligation | $ 100,000 |  |
Status or critical and declining zone plans | 65.00% |  |
Projected insolvent period based on active to inactive participants ratio. | 20 years |  |
Maximum [Member] | Central States, Southeast and Southwest Areas Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expiration dates of collective bargaining arrangements | Feb. 28, 2021 |  |
Percentage representing contribution funded to plan total contribution | 5.00% |  |
Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Projected insolvent period based on active to inactive participants ratio. | 15 years |  |
Minimum [Member] | Central States, Southeast and Southwest Areas Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expiration dates of collective bargaining arrangements | Jan. 31, 2019 |  |
Cash Surrender Value [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash surrender value of plan assets included in other long term assets | $ 4,300,000 | $ 4,200,000 |

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