Segment Information (Reconciliation Of The Company's Consolidated Segment Operating Income To Consolidated Income Before Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 30, 2012	Apr. 01, 2011
Segment Information [Abstract]
Consolidated segment operating income	$ 113,135	$ 77,813
Unallocated corporate expense	(19,280)	(15,118)
Amortization of purchased intangible assets	(28,797)	(16,065)
Acquisition costs	(5,210)	(2,955)
Operating income	59,848	43,675
Non-operating income, net	479	2,606
Income before taxes	$ 60,327	$ 46,281

Segment Reporting Information Amortization Of Purchased Intangible Assets

No definition available.

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- Definition

Segment Reporting Information Consolidated Segment Operating Income

+ References

No definition available.

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- Definition

Segment Reporting Information Unallocated Corporate Expense

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No definition available.

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- Definition

The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 4

-Section 10

-Paragraph c

-Subparagraph 3(ii)(A)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-10.(c)(7)(ii))

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 4

-Section 08

-Paragraph h

-Subparagraph 1(i)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.4-08.(h)(1)(i))

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 7

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7)

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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