Share-Based Compensation (Detail) - Activity in our share-based compensation plans	0 Months Ended	3 Months Ended
Dec. 29, 2012	Mar. 23, 2013
Service Based Grants [Member]
Outstanding Numbers	512,200	517,100
Outstanding, Weighted Average Remaining Restriction/ Vesting Period (Years)	36 days	36 days
Vested Numbers	475,400	480,000
Granted		600
Restrictions lapsed/ units settled		(300)
Shares deferred upon vesting/settlement & dividend equivalents on deferred shares(1)		4,600
Performance Based Grants [Member]
Outstanding Numbers	641,700	926,800
Outstanding, Weighted Average Remaining Restriction/ Vesting Period (Years)	328 days	1 year 146 days
Vested Numbers	303,100	304,400
Granted		295,300
Forfeited/cancelled		(11,500)
Restrictions lapsed/ units settled		(1,500)
Shares deferred upon vesting/settlement & dividend equivalents on deferred shares(1)		2,800

Number of non-option equity instruments deferred upon vesting.

No definition available.

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ 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 (c)(2)(iii)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(d)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Number of shares under non-option equity instrument agreements for which rights to exercise lapsed.

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- Definition

Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

Number of shares reserved for issuance under non-option equity instrument agreements awarded that validly exist and are outstanding, including vested instruments.

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+ Details

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