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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.

+ 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)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

+ Details

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Period Type:	instant

- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Number of shares related to Restricted Stock Award forfeited during the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4, 5

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 5: 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)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

+ Details

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Period Type:	duration

- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ 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 210.5-02.28,29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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Stockholders' Deficiency - Common Stock, Treasury Stock Issued and Outstanding (Detail)	0 Months Ended									12 Months Ended
	Jul. 02, 2012	Jan. 02, 2012	Jan. 10, 2012	Jul. 02, 2011	Jan. 02, 2011	Jan. 10, 2011	Jul. 02, 2010	Jan. 02, 2010	Jan. 10, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Class of Stock [Line Items]
Beginning Balance		671,271	671,271		532,838	532,838		385,677	385,677	671,271	532,838	385,677
Cancellation of restricted stock
Withholding of restricted stock to satisfy taxes	3,953	594	79,035	4,121	52,138	82,174	4,121	55,159	87,881	83,582	138,433	147,161
Ending Balance										754,853	671,271	532,838
Class A Common Stock [Member]
Class of Stock [Line Items]
Beginning Balance		49,986,651	49,986,651		50,000,497	50,000,497		50,021,063	50,021,063	49,986,651	50,000,497	50,021,063
Cancellation of restricted stock											(13,846)	(20,566)
Withholding of restricted stock to satisfy taxes
Ending Balance										49,986,651	49,986,651	50,000,497
Class B Common Stock [Member]
Class of Stock [Line Items]
Beginning Balance		3,125,000	3,125,000		3,125,000	3,125,000		3,125,000	3,125,000	3,125,000	3,125,000	3,125,000
Cancellation of restricted stock
Withholding of restricted stock to satisfy taxes
Ending Balance										3,125,000	3,125,000	3,125,000