Shareholders' Equity (Employee Stock-Based Compensation Expense Included in the Consolidated Statements of Income) (Details) (USD $) In Thousands	3 Months Ended				6 Months Ended
	Jul. 01, 2011		Jul. 02, 2010		Jul. 01, 2011		Jul. 02, 2010
Total stock-based compensation expense	$ 7,129		$ 4,984		$ 13,927		$ 10,625
Tax benefit	(2,139)	[1]	(1,419)	[1]	(4,342)	[1]	(2,195)	[1]
Total stock-based compensation expense, net of tax	4,990		3,565		9,585		8,430
Cost of Sales [Member]
Total stock-based compensation expense	502		486		970		987
Research and Development [Member]
Total stock-based compensation expense	1,126		984		2,222		1,931
Sales and Marketing [Member]
Total stock-based compensation expense	1,659		1,347		3,293		2,730
General and Administrative [Member]
Total stock-based compensation expense	3,842		2,167		7,442		4,977
Total Operating Expenses [Member]
Total stock-based compensation expense	$ 6,627		$ 4,498		$ 12,957		$ 9,638

[1] Tax benefit related to U.S. non-qualified options, restricted stock units, and disqualified disposition of incentive stock options, applying a Federal statutory and State (Federal effected) tax rate for the respective periods.