Segment Information (Reconciliation Of The Company's Consolidated Segment Operating Income To Consolidated Income Before Income Taxes) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Oct. 01, 2010	Sep. 30, 2011	Oct. 01, 2010
Segment Information [Abstract]
Consolidated segment operating income	$ 80,137	$ 61,606	$ 247,404	$ 195,656
Unallocated corporate expense	(16,302)	(14,935)	(50,192)	(42,074)
Amortization of purchased intangible assets	(24,106)	(14,432)	(56,747)	(42,165)
Acquisition cost	(7,281)	(569)	(12,775)	(3,071)
Operating income	32,448	31,670	127,690	108,346
Non-operating income (expense), net	(2,563)	6,659	8,674	10,480
Income before taxes	$ 29,885	$ 38,329	$ 136,364	$ 118,826

Segment Reporting Information Amortization Of Purchased Intangible Assets

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Segment Reporting Information Consolidated Segment Operating Income

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Segment Reporting Information Unallocated Corporate Expense

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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.

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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.

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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).

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