Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 26, 2015	Mar. 28, 2015
Available-for-sale securities
Amortized Cost	$ 3,397,059	$ 3,471,735
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	11,018	10,961
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(19,895)	(11,340)
Estimated Fair Value	3,388,182	3,471,356
Money Market Funds [Member]
Available-for-sale securities
Amortized Cost	203,815	235,583
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Estimated Fair Value	203,815	235,583
Financial institution securities [Member]
Available-for-sale securities
Amortized Cost	300,006	304,999
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Estimated Fair Value	300,006	304,999
Non-financial institution securities [Member]
Available-for-sale securities
Amortized Cost	471,681	429,005
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	82	25
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(232)	(6)
Estimated Fair Value	471,531	429,024
Auction Rate Securities [Member]
Available-for-sale securities
Amortized Cost	10,500	10,500
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(87)	(188)
Estimated Fair Value	10,413	10,312
Municipal Bonds [Member]
Available-for-sale securities
Amortized Cost	62,776	49,064
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	584	744
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(246)	(152)
Estimated Fair Value	63,114	49,656
U.S. Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	451,441	757,954
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	144	91
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(7)	(129)
Estimated Fair Value	451,578	757,916
Foreign Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	201,481	197,932
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Estimated Fair Value	201,481	197,932
Mortgage-Backed Securities [Member]
Available-for-sale securities
Amortized Cost	1,116,561	1,075,730
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	8,489	8,942
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(4,845)	(4,496)
Estimated Fair Value	1,120,205	1,080,176
Asset-backed Securities [Member]
Available-for-sale securities
Amortized Cost	214,120	211,487
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	1,251	1,130
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(523)	(159)
Estimated Fair Value	214,848	212,458
Debt Mutual Fund [Member]
Available-for-sale securities
Amortized Cost	101,350	101,350
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(13,029)	(6,150)
Estimated Fair Value	88,321	95,200
Bank Loans [Member]
Available-for-sale securities
Amortized Cost	104,101	98,131
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	44	29
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(93)	(60)
Estimated Fair Value	104,052	98,100
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities
Amortized Cost	159,227	0
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	424	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(833)	0
Estimated Fair Value	$ 158,818	$ 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

-Topic 320

-SubTopic 10

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