Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified	Mar. 28, 2015	Mar. 29, 2014
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	$ 1,095,972	$ 751,113
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	5,009	13,394
Available-for-Sale Securities, 12 Months or Greater, Fair Value	118,042	158,767
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	6,331	4,759
Available-for-Sale Securities, Fair Value, Total	1,214,014	909,880
Available-for-Sale Securities, Gross Unrealized Losses, Total	(11,340)	(18,153)
Non-financial institution securities [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	7,190	112,470
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	6	1,167
Available-for-Sale Securities, 12 Months or Greater, Fair Value	0	4,488
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	77
Available-for-Sale Securities, Fair Value, Total	7,190	116,958
Available-for-Sale Securities, Gross Unrealized Losses, Total	(6)	(1,244)
Auction Rate Securities [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Available-for-Sale Securities, 12 Months or Greater, Fair Value	10,312	20,160
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	188	1,340
Available-for-Sale Securities, Fair Value, Total	10,312	20,160
Available-for-Sale Securities, Gross Unrealized Losses, Total	(188)	(1,340)
Municipal Bonds [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	10,014	5,917
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	94	166
Available-for-Sale Securities, 12 Months or Greater, Fair Value	1,931	1,743
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	58	39
Available-for-Sale Securities, Fair Value, Total	11,945	7,660
Available-for-Sale Securities, Gross Unrealized Losses, Total	(152)	(205)
U.S. Government and Agency Securities [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	451,296	118,125
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	129	184
Available-for-Sale Securities, 12 Months or Greater, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Available-for-Sale Securities, Fair Value, Total	451,296	118,125
Available-for-Sale Securities, Gross Unrealized Losses, Total	(129)	(184)
Mortgage-Backed Securities [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	448,770	457,903
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	3,169	7,225
Available-for-Sale Securities, 12 Months or Greater, Fair Value	49,207	132,376
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1,327	3,303
Available-for-Sale Securities, Fair Value, Total	497,977	590,279
Available-for-Sale Securities, Gross Unrealized Losses, Total	(4,496)	(10,528)
Asset-backed Securities [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	75,009
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	159
Available-for-Sale Securities, 12 Months or Greater, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Available-for-Sale Securities, Fair Value, Total	75,009
Available-for-Sale Securities, Gross Unrealized Losses, Total	(159)
Debt Mutual Fund [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	38,608	56,698
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,392	4,652
Available-for-Sale Securities, 12 Months or Greater, Fair Value	56,592	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	4,758	0
Available-for-Sale Securities, Fair Value, Total	95,200	56,698
Available-for-Sale Securities, Gross Unrealized Losses, Total	(6,150)	(4,652)
Bank Loans [Member]
Fair values and gross unrealized losses of the investments
Available-for-Sale Securities, Less Than 12 Months, Fair Value	65,085
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	60
Available-for-Sale Securities, 12 Months or Greater, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Available-for-Sale Securities, Fair Value, Total	65,085
Available-for-Sale Securities, Gross Unrealized Losses, Total	$ (60)

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

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