Condensed Consolidated Balance Sheet (Parenthetical) (USD $) In Thousands, except Share data	Jun. 26, 2011	Dec. 26, 2010
Trade receivables, allowance	$ 7,431	$ 7,836
Common stock, par value	$ 0.01	$ 0.01
Treasury stock, shares	258,862	116,045
Common Class A [Member]
Shares authorized	200,000,000	200,000,000
Shares issued	60,575,222	60,278,448
Common Class B [Member]
Shares authorized	60,000,000	60,000,000
Shares issued	24,800,962	24,800,962

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 4
-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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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-Paragraph 30
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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
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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.

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-Name Regulation S-X (SX)
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