Cash, Cash Equivalents, and Investments - Gross Unrealized Losses and Fair Values for Available-for-Sale Investments (Detail) $ in Thousands	Jul. 01, 2018 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	$ 350,445
Unrealized losses, less than 12 months	(1,392)
Fair value, 12 months or greater	80,415
Unrealized losses, 12 months or greater	(491)
Total fair value	430,860
Total unrealized losses	(1,883)
Treasury Bills
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	84,309
Unrealized losses, less than 12 months	(149)
Fair value, 12 months or greater	48,464
Unrealized losses, 12 months or greater	(183)
Total fair value	132,773
Total unrealized losses	(332)
Asset-Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	90,411
Unrealized losses, less than 12 months	(496)
Fair value, 12 months or greater	4,462
Unrealized losses, 12 months or greater	(28)
Total fair value	94,873
Total unrealized losses	(524)
Sovereign Bonds
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	3,562
Unrealized losses, less than 12 months	(9)
Fair value, 12 months or greater	4,581
Unrealized losses, 12 months or greater	(58)
Total fair value	8,143
Total unrealized losses	(67)
Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	3,692
Unrealized losses, less than 12 months	(24)
Fair value, 12 months or greater	0
Unrealized losses, 12 months or greater	0
Total fair value	3,692
Total unrealized losses	(24)
Agency Bonds
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	29,246
Unrealized losses, less than 12 months	(1)
Fair value, 12 months or greater	0
Unrealized losses, 12 months or greater	0
Total fair value	29,246
Total unrealized losses	(1)
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	139,225
Unrealized losses, less than 12 months	(713)
Fair value, 12 months or greater	22,908
Unrealized losses, 12 months or greater	(222)
Total fair value	162,133
Total unrealized losses	$ (935)