Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Jun. 29, 2013	Mar. 30, 2013
Available-for-sale securities
Amortized Cost	$ 3,442,007	$ 3,272,432
Gross Unrealized Gains	12,268	25,316
Gross Unrealized Losses	(22,984)	(8,527)
Estimated Fair Value	3,431,291	3,289,221
Money Market Funds [Member]
Available-for-sale securities
Amortized Cost	178,579	108,311
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	178,579	108,311
Bank Certificates of Deposit [Member]
Available-for-sale securities
Amortized Cost	154,985	124,987
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	154,985	124,987
Commercial Paper [Member]
Available-for-sale securities
Amortized Cost	491,249	503,550
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	491,249	503,550
Corporate Bonds [Member]
Available-for-sale securities
Amortized Cost	263,696	270,945
Gross Unrealized Gains	2,291	5,193
Gross Unrealized Losses	(3,156)	(135)
Estimated Fair Value	262,831	276,003
Auction Rate Securities [Member]
Available-for-sale securities
Amortized Cost	31,500	31,900
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2,254)	(3,200)
Estimated Fair Value	29,246	28,700
Municipal Bonds [Member]
Available-for-sale securities
Amortized Cost	21,897	24,496
Gross Unrealized Gains	356	514
Gross Unrealized Losses	(284)	(70)
Estimated Fair Value	21,969	24,940
U.S. Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	872,223	696,836
Gross Unrealized Gains	254	431
Gross Unrealized Losses	(317)	(45)
Estimated Fair Value	872,160	697,222
Foreign Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	224,916	269,901
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	224,916	269,901
Mortgage-Backed Securities [Member]
Available-for-sale securities
Amortized Cost	1,141,612	1,180,156
Gross Unrealized Gains	9,367	17,601
Gross Unrealized Losses	(15,240)	(5,077)
Estimated Fair Value	1,135,739	1,192,680
Debt Mutual Fund [Member]
Available-for-sale securities
Amortized Cost	61,350	61,350
Gross Unrealized Gains	0	1,577
Gross Unrealized Losses	(1,733)	0
Estimated Fair Value	$ 59,617	$ 62,927