Net Income Per Share (Details) (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jul. 02, 2011	Jul. 03, 2010	Jul. 02, 2011	Jul. 03, 2010
Basic and diluted net income per share
Net income	$ 26,908	$ 48,607	$ 33,231	$ 36,822
Weighted average common shares used to calculate basic net income per share	263,191	262,163	262,362	262,380
2023 Notes	11	11	11	11
Options	3,766	1,482	3,487	1,275
Restricted stock	3,740	2,522	3,744	2,658
Employee stock purchase plan (ESPP)	177	245	128	215
Weighted average common shares outstanding - diluted	270,885	266,423	269,732	266,539
Basic net income per share	$ 0.10	$ 0.19	$ 0.13	$ 0.14
Diluted net income per share	$ 0.10	$ 0.18	$ 0.12	$ 0.14

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