Segment Information (Reconciliation Of Company's Consolidated Segment Operating Income To Consolidated Income Before Income Taxes) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 29, 2012	Jul. 01, 2011	Jun. 29, 2012	Jul. 01, 2011
Segment Reporting Information [Line Items]
Consolidated segment operating income	$ 115,633	$ 89,453	$ 228,768	$ 167,266
Unallocated corporate expense	(19,819)	(18,006)	(39,543)	(33,889)
Amortization of purchased intangible assets	(29,078)	(16,576)	(57,875)	(32,641)
Acquisition costs	(7,815)	(3,304)	(12,581)	(5,494)
Consolidated operating income	58,921	51,567	118,769	95,242
Non-operating income, net	4,370	8,631	4,849	11,237
Consolidated income before taxes	$ 63,291	$ 60,198	$ 123,618	$ 106,479

Segment Reporting Information Consolidated Segment Operating Income

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- Definition

Segment Reporting Information Unallocated Corporate Expense

+ References

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 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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 10

-Paragraph c

-Subparagraph 3(ii)(A)

-Article 4

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- Definition

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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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 FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

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

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-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 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 FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

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

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