Earnings Per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
Jul. 02, 2011	Jul. 03, 2010	Jul. 02, 2011	Jul. 03, 2010
Earnings Per Share Reconciliation [Abstract]
Net income	$ 100,075	$ 84,922	$ 194,564	$ 160,440
Net income per basic common share	$ 1.09	$ 0.92	$ 2.12	$ 1.72
Net income per diluted common share	$ 1.07	$ 0.90	$ 2.09	$ 1.69
Weighted-average number of basic common shares	91,662,000	92,612,000	91,649,000	93,110,000
Effect of dilutive stock option, restricted stock and restricted stock unit securities	1,609,000	1,666,000	1,653,000	1,643,000
Weighted-average number of diluted common shares and equivalents	93,271,000	94,278,000	93,302,000	94,753,000
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	700,000	1,800,000	700,000	1,900,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
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The amount of income (loss) from continuing operations per each share of common stock outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The amount of income (loss) from continuing operations available to each share of common stock outstanding during the reporting period and each share that would have been outstanding assuming the issuance of common shares for all dilutive potential common shares outstanding during the reporting period.

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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period.

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Includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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