Marketable Securities (Details) (USD $) In Thousands	Oct. 02, 2011	Apr. 03, 2011
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	$ 315,966	$ 235,447
Available-for-sale securities, Gross Unrealized Gains	1,290	1,409
Available-for-sale securities, Gross Unrealized Losses	(989)	(560)
Available-for-sale securities, Estimated Fair Value	316,267	236,296
U.S. Government and agency securities [Member]
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	84,825	55,875
Available-for-sale securities, Gross Unrealized Gains	188	94
Available-for-sale securities, Gross Unrealized Losses	(32)	(216)
Available-for-sale securities, Estimated Fair Value	84,981	55,753
Corporate debt obligations [Member]
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	178,358	137,706
Available-for-sale securities, Gross Unrealized Gains	868	1,012
Available-for-sale securities, Gross Unrealized Losses	(872)	(282)
Available-for-sale securities, Estimated Fair Value	178,354	138,436
Asset and mortgage-backed securities [Member]
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	29,769	22,249
Available-for-sale securities, Gross Unrealized Gains	200	293
Available-for-sale securities, Gross Unrealized Losses	(80)	(52)
Available-for-sale securities, Estimated Fair Value	29,889	22,490
Municipal bonds [Member]
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	21,153	17,941
Available-for-sale securities, Gross Unrealized Gains	34	10
Available-for-sale securities, Gross Unrealized Losses	(5)	(10)
Available-for-sale securities, Estimated Fair Value	21,182	17,941
Non-U.S. government and agency securities [Member]
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	1,652	1,676
Available-for-sale securities, Gross Unrealized Gains	0	0
Available-for-sale securities, Gross Unrealized Losses	0	0
Available-for-sale securities, Estimated Fair Value	1,652	1,676
Total debt securities [Member]
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	315,757
Available-for-sale securities, Gross Unrealized Gains	1,290
Available-for-sale securities, Gross Unrealized Losses	(989)
Available-for-sale securities, Estimated Fair Value	316,058
Certificates of deposit [Member]
Schedule of Available-For-Sale Securities
Available-for-sale securities, Amortized Cost	209
Available-for-sale securities, Gross Unrealized Gains	0
Available-for-sale securities, Gross Unrealized Losses	0
Available-for-sale securities, Estimated Fair Value	$ 209

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References+ Details