Stock-Based Compensation (Performance-Contingent Return on Invested Capital Shares) - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 29, 2018 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Return on investment target over the two fiscal years immediately preceding the vesting date	1.75%
Percentage of shares that can be earned	0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Return on investment target over the two fiscal years immediately preceding the vesting date	4.75%
Percentage of shares that can be earned	125.00%
Maximum \| 2017 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares that can be earned	80.00%
Weighted Average Cost of Capital \| Range One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	50.00%
Weighted Average Cost of Capital \| Range Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	100.00%
Weighted Average Cost of Capital \| Range Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	125.00%
Return On Invested Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout	0.00%
Return On Invested Capital \| Range One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	1.75%
Return On Invested Capital \| Range Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	3.75%
Return On Invested Capital \| Range Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	4.75%
Performance Contingent Return On Invested Capital Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested restricted stock granted by the EPIP \| $	$ 0.5
Expected weighted-average period to recognize compensation cost (years)	2 months 1 day
Shares granted \| shares	0
Performance Contingent Return On Invested Capital Shares \| Performance contingent Awards 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	18 months
Performance Contingent Return On Invested Capital Shares \| Performance contingent Awards subsequent to 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years

Range of Percentage Of Target Incentive Required Payout

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Range of payout in percentage of target shares possible to earn.

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Range of Performance Share Payout

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Return On Investment Share Based Compensation Arrangement By Share Based Payment Award Performance Condition target Percentage in excess of weighted average cost of capital.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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