Share Repurchases (Details) (USD $) In Thousands, except Per Share data	6 Months Ended
Jul. 02, 2011	Jul. 03, 2010
Share Repurchases
Cumulative balance, Shares, Beginning Balance	23,713	15,095
Cumulative balance, Weighted Average Price Per Share, Beginning Balance	$ 16.40	$ 16.11
Cumulative balance, Net Amount, Beginning Balance	$ 388,817	$ 243,219
Repurchase of Class A Common Stock, Shares	4,081	8,960
Repurchase of Class A Common Stock, Weighted Average Price Per Share	$ 18.60	$ 16.99
Repurchase of Class A Common Stock	75,906	152,285
Issuance of shares of Class A Common Stock, Weighted Average Price Per Share	$ 19.00	$ 19.67
Issuance of shares of Class A Common Stock, Shares	(538)	(225)
Issuance of shares of Class A Common Stock, Net Amount	(10,221)	(4,435)
Cumulative balance, Shares, Ending Balance	27,256	23,830
Cumulative balance, Weighted Per Share Average, Ending Balance	$ 16.68	$ 16.41
Cumulative balance, Net Amount, Ending Balance	$ 454,502	$ 391,069

Issued shares of common stock weighted average price per share.

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- Definition

Treasury Stock Weighted Average Price Per Share.

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- Definition

The cash outflow to reacquire common stock during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 20
-Subparagraph a

+ Details

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- Definition

Number of treasury shares reissued during the period. Upon reissuance, these are common and preferred shares outstanding.

+ References

+ Details

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- Definition

Value of treasury stock reissued during the period. Upon reissuance, common and preferred stock are outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 1
-Section B
-Paragraph 7
-Subparagraph b

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 1
-Section B
-Paragraph 7
-Subparagraph b

+ Details

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- Details

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- 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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

+ Details

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: 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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- Definition

Value of common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. Treasury stock is issued but is not outstanding. This stock has no voting rights and receives no dividends. Note that treasury stock may be recorded at its total cost or separately as par (or stated) value and additional paid in capital. Note: number of treasury shares concept is in another section within stockholders' equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Technical Bulletin (FTB)
-Number 85-6
-Paragraph 3

+ Details

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