Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 27, 2015	Mar. 28, 2015
Available-for-sale securities
Amortized Cost	$ 3,477,372	$ 3,471,735
Gross Unrealized Gains	9,582	10,961
Gross Unrealized Losses	18,044	11,340
Estimated Fair Value	3,468,910	3,471,356
Money Market Funds [Member]
Available-for-sale securities
Amortized Cost	304,935	235,583
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	304,935	235,583
Financial institution securities [Member]
Available-for-sale securities
Amortized Cost	290,000	304,999
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	290,000	304,999
Non-financial institution securities [Member]
Available-for-sale securities
Amortized Cost	425,413	429,005
Gross Unrealized Gains	44	25
Gross Unrealized Losses	80	6
Estimated Fair Value	425,377	429,024
Auction Rate Securities [Member]
Available-for-sale securities
Amortized Cost	10,500	10,500
Gross Unrealized Gains	0	0
Gross Unrealized Losses	91	188
Estimated Fair Value	10,409	10,312
Municipal Bonds [Member]
Available-for-sale securities
Amortized Cost	53,839	49,064
Gross Unrealized Gains	552	744
Gross Unrealized Losses	338	152
Estimated Fair Value	54,053	49,656
U.S. Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	575,867	757,954
Gross Unrealized Gains	142	91
Gross Unrealized Losses	46	129
Estimated Fair Value	575,963	757,916
Foreign Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	201,045	197,932
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	201,045	197,932
Mortgage-Backed Securities [Member]
Available-for-sale securities
Amortized Cost	1,091,058	1,075,730
Gross Unrealized Gains	6,358	8,942
Gross Unrealized Losses	9,467	4,496
Estimated Fair Value	1,087,949	1,080,176
Asset-backed Securities [Member]
Available-for-sale securities
Amortized Cost	219,682	211,487
Gross Unrealized Gains	958	1,130
Gross Unrealized Losses	331	159
Estimated Fair Value	220,309	212,458
Debt Mutual Fund [Member]
Available-for-sale securities
Amortized Cost	101,350	101,350
Gross Unrealized Gains	0	0
Gross Unrealized Losses	7,002	6,150
Estimated Fair Value	94,348	95,200
Bank Loans [Member]
Available-for-sale securities
Amortized Cost	98,564	98,131
Gross Unrealized Gains	1,350	29
Gross Unrealized Losses	79	60
Estimated Fair Value	99,835	98,100
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities
Amortized Cost	105,119	0
Gross Unrealized Gains	178	0
Gross Unrealized Losses	610	0
Estimated Fair Value	$ 104,687	$ 0

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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