Marketable Securities (Schedule of Cost And Estimated Fair Value Of Available-for-sale Securities By Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 28, 2013	Mar. 30, 2013
Marketable Securities [Abstract]
Within 1 year, Amortized Cost	$ 215,742	$ 105,290
After 1 year, Amortized Cost	37,163	65,004
Within 1 year, Estimated Fair Value	215,792	105,235
After 1 year, Estimated Fair Value	37,115	64,910
Amortized Cost	252,905	170,294
Estimated Fair Value	$ 252,907	$ 170,145