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Associate Retirement Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Jan. 02, 2021 | Dec. 28, 2019 | Dec. 29, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined contribution plans expense | $ 12,200,000 | $ 11,500,000 | $ 7,000,000.0
Cash surrender value of plan assets included in other long term assets | 99,242,000 | 82,660,000 |
Aggregate amount of life insurance coverage | $ 15,000,000.0 | 15,000,000.0 |
Defined contribution plan employees minimum period of service | 10 years |  |
Defined contribution plan employees age to eligible under the plan | 55 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% |  |
Multiemployer plans, certified zone status | Red |  |
Critical and declining zone fund status | Less than 65 percent |  |
Maximum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Status or critical and declining zone plans | 65.00% |  |
Projected insolvent period based on active to inactive participants ratio. | 20 years |  |
Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Projected insolvent period based on active to inactive participants ratio. | 15 years |  |
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 | $ 13,700,000 | 13,800,000 | 13,800,000
Central States, Southeast and Southwest Areas Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension contributions during last plan year | $ 14,100,000 | 14,000,000.0 | 13,300,000
Collective bargaining arrangement description | The Company is party to four CBAs that require contributions to the Plan with expiration dates ranging from January 2022 to October 2022. These CBAs cover warehouse personnel and drivers in Grand Rapids, Michigan and Bellefontaine and Lima, Ohio. |  |
Central States, Southeast and Southwest Areas Pension Plan [Member] | Maximum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expiration dates of collective bargaining arrangements | Oct. 31, 2022 |  |
Percentage representing contribution funded to plan total contribution | 5.00% |  |
Central States, Southeast and Southwest Areas Pension Plan [Member] | Minimum [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expiration dates of collective bargaining arrangements | Jan. 31, 2022 |  |
Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined contribution plans expense |  | 1,500,000 |
Frozen pension plan, termination date | Jul. 31, 2018 |  |
Realized gains related to refunds from annuity provider | $ 1,193,000 |  |
Pre-tax settlement charges |  | 18,200,000 |
Defined benefit termination plan |  | 18,000,000.0 |
Distribution charges |  | 72,600,000 | 3,300,000
Settlement accounting charges |  | 18,244,000 | 785,000
Fair value of plan assets | 2,689,000 | 1,496,000 | $ 74,241,000
Pension Plan [Member] | Significant unobservable inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Pension Plan [Member] | Money Market Funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,700,000 | 1,500,000 |
Retiree Medical Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expected Company contribution in 2021 | 500,000 |  |
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 | $ 4,300,000 |

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