Income per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Apr. 01, 2012	Apr. 03, 2011
Numerator:
Income from continuing operations	$ 24,275	$ 22,018
Loss from discontinued operations, net of tax		(128)
Net income	$ 24,275	$ 21,890
Denominator:
Weighted average shares outstanding, basic	45,912	47,209
Effect of dilutive common stock equivalents	1,026	1,121
Weighted average shares outstanding, diluted	46,938	48,330
Income per Share (Textual) [Abstract]
Diluted weighted average shares outstanding do not include outstanding equity awards	700,000	400,000

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Antidilution

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-Name Statement of Financial Accounting Standard (FAS)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

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-Publisher FASB

-Name Accounting Standards Codification

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-Glossary Contingent Stock Agreement

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- Definition

This element represents the income or loss from continuing operations attributable to the parent which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests, if any.

+ References

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

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- Definition

This element represents the overall income (loss) from a disposal group apportioned to the parent that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Glossary Other Comprehensive Income

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

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

+ References

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