Stock-Based Compensation (Performance-Contingent Total Shareholder Return Shares) - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 30, 2017 USD ($)
Performance Contingent Total Shareholders Return Shares \| Performance contingent Awards 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	18 months
Performance Contingent Total Shareholders Return Shares \| Performance contingent Awards Granted Subsequent To 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Total Shareholders Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, fair value assumptions, method used	Inputs into the model included the following for the company and comparator companies: (i) TSR from the beginning of the performance cycle through the measurement date; (ii) volatility; (iii) risk-free interest rates; and (iv) the correlation of the comparator companies’ TSR. The inputs are based on historical capital market data.
Total Shareholders Return \| Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested restricted stock granted by the EPIP	$ 5.6
Expected weighted-average period to recognize compensation cost (years)	1 year 25 days

Vesting period for return on invested capital awards issued after 2012.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

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- Definition

For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

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