Common stock shares issued and outstanding.

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- Definition

Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Year

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- Definition

Income Tax Benefit From Restricted Stock

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- Definition

Maximum percentage of issued shares to outstanding shares.

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No definition available.

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- Definition

Number Of Authorized Stock Reduce By Issuance Of Other Than Stock Option Award

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Exercisable Period

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Expiration Period

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- Definition

Share based compensation arrangement by share based payment award unvested stock options awards weighted average period in years.

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No definition available.

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- Definition

Stock Based Compensation Rate At Which Employee Stock Option Exercisable

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ 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 (h)(1)(i)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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- Definition

Issuance value per share of no-par value common stock; generally not indicative of the fair market value per share.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4

-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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

+ References

No definition available.

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- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph i

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 19

-Subparagraph a

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 18

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (j)

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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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).

+ References

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(1)

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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Shareholders' Equity - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended				12 Months Ended
	Dec. 30, 2012	Jan. 01, 2012	Jan. 02, 2011	May 31, 2010	Dec. 30, 2012 Restricted stock [Member]	Jan. 01, 2012 Restricted stock [Member]	Jan. 02, 2011 Restricted stock [Member]	Dec. 30, 2012 Minimum [Member]	Dec. 30, 2012 Maximum [Member]	Dec. 30, 2012 Class A Common Stock [Member]	Dec. 30, 2012 Class B Common Stock [Member]	Mar. 05, 2012 Class B Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized Common Stock										80,000,000	40,000,000	120,000,000
Par Value of Common Stock										$ 0.10	$ 0.10
Number of shares issued and outstanding												6,459,556
Aggregate number of shares issued and outstanding												65,372,375
Maximum percentage of issued shares to outstanding shares												Less than 10%
Common Stock par value												$ 0.10
Common stock dividend	$ 0.0900	$ 0.0800	$ 0.0425
Option exercise period								1 year	5 years
Options expiry period								3 years	10 years
Transfer of shares				6,558,263
Stock option authorized				1.33
Options exercisable at fair market value for Shares of Class A or Class B	100.00%
Stock option compensation costs	$ 0.5	$ 0.8	$ 1.2
Weighted average period for unrecognized compensation cost to be recognized	1 year	1 year
Unrecognized total compensation cost related to unvested restricted stock	0.1
Weighted average fair value of stock options		$ 7.37	$ 6.86
Aggregate intrinsic value of in-the-money options outstanding	2.9
Aggregate intrinsic value of option exercisable	2.9
Intrinsic value of stock options exercised	0.9	6.0	5.5
Cash proceed related to stock options	1.5	2.7	3.1
Restricted stock awards	573,000	668,000	529,000		573,000
Awards vest with respect to each recipient								2 years	5 years
Compensation expense related to restricted stock grants	3.3	10.1	2.9
Unrecognized total compensation cost related to unvested restricted stock	9.9
Unrecognized total compensation cost related to unvested restricted stock end period	2015
Tax benefit recognized with respect to restricted stock					$ 0.7	$ 2.8	$ 0.7