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Associate Retirement Plans - Assumed Current Healthcare Cost Trend Rates Used to Determine Net Periodic Benefit Cost (Income) (Detail) | 12 Months Ended
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Dec. 29, 2018 | Dec. 30, 2017 | Dec. 31, 2016
Defined Benefit Plan Assumed Health Care Cost Trend Rates [Abstract] |  |  |
Pre-65 |  |  | 7.50%
Post-65 | 8.00% | 8.40% | 8.40%

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- Definition Defined benefit plan health care cost trend rate assumed for post sixty five year age. + References No definition available. + Details
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- Definition Defined benefit plan health care cost trend rate assumed for pre sixty five year age. + References No definition available. + Details
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- References No definition available. + Details
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