Marketable Securities (Details 2) (USD $) In Thousands, unless otherwise specified	Jan. 01, 2012	Apr. 03, 2011
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	$ 131,166	$ 96,164
Unrealized losses of less than 12 months	(631)	(560)
Fair Value of 12 months or greater	327	0
Unrealized losses of 12 months or Greater	(2)	0
Fair value, Total	131,493	96,164
Unrealized losses, Total	(633)	(560)
U.S. Government and agency securities [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	48,183	25,712
Unrealized losses of less than 12 months	(27)	(216)
Fair Value of 12 months or greater	0	0
Unrealized losses of 12 months or Greater	0	0
Fair value, Total	48,183	25,712
Unrealized losses, Total	(27)	(216)
Corporate debt obligations [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	65,975	60,595
Unrealized losses of less than 12 months	(529)	(282)
Fair Value of 12 months or greater	327	0
Unrealized losses of 12 months or Greater	(2)	0
Fair value, Total	66,302	60,595
Unrealized losses, Total	(531)	(282)
Asset and mortgage-backed securities [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	14,935	7,991
Unrealized losses of less than 12 months	(73)	(52)
Fair Value of 12 months or greater	0	0
Unrealized losses of 12 months or Greater	0	0
Fair value, Total	14,935	7,991
Unrealized losses, Total	(73)	(52)
Municipal bonds [Member]
Schedule of Unrealized Losses by Investment Category
Fair value of less than 12 months	2,073	1,866
Unrealized losses of less than 12 months	(2)	(10)
Fair Value of 12 months or greater	0	0
Unrealized losses of 12 months or Greater	0	0
Fair value, Total	2,073	1,866
Unrealized losses, Total	$ (2)	$ (10)