Investments - Unrealized Loss (Details) - USD ($) $ in Thousands	Jul. 02, 2017	Apr. 02, 2017
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Fair Value Less than 12 months	$ 138,863	$ 140,733
Unrealized Loss Less than 12 months	(767)	(872)
Fair Value 12 months or Greater	0	0
Unrealized Loss 12 months or Greater	0	0
Fair Value Total	138,863	140,733
Unrealized Loss Total	(767)	(872)
Corporate bonds
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Fair Value Less than 12 months	58,957	71,308
Unrealized Loss Less than 12 months	(226)	(326)
Fair Value 12 months or Greater	0	0
Unrealized Loss 12 months or Greater	0	0
Fair Value Total	58,957	71,308
Unrealized Loss Total	(226)	(326)
Asset-backed securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Fair Value Less than 12 months	8,958	11,294
Unrealized Loss Less than 12 months	(19)	(23)
Fair Value 12 months or Greater	0	0
Unrealized Loss 12 months or Greater	0	0
Fair Value Total	8,958	11,294
Unrealized Loss Total	(19)	(23)
U.S. government treasuries and agencies securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Fair Value Less than 12 months	68,311	55,497
Unrealized Loss Less than 12 months	(509)	(508)
Fair Value 12 months or Greater	0	0
Unrealized Loss 12 months or Greater	0	0
Fair Value Total	68,311	55,497
Unrealized Loss Total	(509)	(508)
International government bonds
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract]
Fair Value Less than 12 months	2,637	2,634
Unrealized Loss Less than 12 months	(13)	(15)
Fair Value 12 months or Greater	0	0
Unrealized Loss 12 months or Greater	0	0
Fair Value Total	2,637	2,634
Unrealized Loss Total	$ (13)	$ (15)