Stock-Based Compensation (Performance-Contingent Return on Invested Capital Shares) - Additional Information (Detail)	4 Months Ended
Apr. 21, 2018
Return On Invested Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	1.75%
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%
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%
Maximum \| 2017 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares being expensed	100.00%
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%
Weighted Average Cost of Capital \| Return On Invested Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout, ROIC above WACC	0.00%
Minimum [Member]
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%
Performance Contingent Return On Invested Capital Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Performance Contingent Return On Invested Capital Shares \| 2015 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of actual ROI attainment	87.00%
Performance Contingent Return On Invested Capital Shares \| 2016 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of actual ROI attainment	70.00%
Performance Contingent Return On Invested Capital Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares that can be earned	125.00%
Performance Contingent Return On Invested Capital Shares \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares that can be earned	0.00%

Actual Percentage earned on 2012 return on invested capital award

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Range of Percentage Of Target Incentive Required Payout

+ References

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- Definition

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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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.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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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