Marketable Securities (Details 1) (USD $) In Thousands	Oct. 02, 2011
Schedule of Amortized Cost and Estimated Fair Value of Debt Securities
Due in one year or less, Amortized Cost	$ 101,865
Due after one year through three years, Amortized Cost	147,834
Due after three years through five years, Amortized Cost	26,136
Due after five years, Amortized Cost	39,922
Total amortized cost of debt securities	315,757
Due in one year or less, Estimated Fair Value	102,121
Due after one year through three years, Estimated Fair Value	147,833
Due after three years through five years, Estimated Fair Value	26,065
Due after five years, Estimated Fair Value	40,039
Total estimated fair value of debt securities	$ 316,058

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