Cash, Cash Equivalents, and Short-term Investments - Summary of Short-term Investments (Details) - USD ($)	Dec. 30, 2017	Jul. 01, 2017
Cash and Cash Equivalents [Line Items]
Amortized Cost	$ 423,100,000	$ 282,400,000
Gross Unrealized Gains	100,000	0
Gross Unrealized Losses	(800,000)	0
Fair Value	422,400,000	282,400,000
Fair value of short-term investments in unrealized loss position less than 12 months	373,000,000
Fair value of short-term investments in unrealized loss position greater than 12 months	0
Certificates of deposit
Cash and Cash Equivalents [Line Items]
Amortized Cost	23,200,000	202,100,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	23,200,000	202,100,000
Commercial paper
Cash and Cash Equivalents [Line Items]
Amortized Cost	35,300,000
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	35,300,000
Asset-backed securities
Cash and Cash Equivalents [Line Items]
Amortized Cost	89,100,000	26,100,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(100,000)	0
Fair Value	89,000,000	26,100,000
Corporate debt securities
Cash and Cash Equivalents [Line Items]
Amortized Cost	263,100,000	46,400,000
Gross Unrealized Gains	100,000	0
Gross Unrealized Losses	(700,000)	0
Fair Value	262,500,000	46,400,000
Municipal bonds
Cash and Cash Equivalents [Line Items]
Amortized Cost	5,800,000	4,900,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	5,800,000	4,900,000
Mortgage-backed securities
Cash and Cash Equivalents [Line Items]
Amortized Cost	1,000,000	1,000,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1,000,000	1,000,000
Foreign government bonds
Cash and Cash Equivalents [Line Items]
Amortized Cost	5,600,000
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	$ 5,600,000
U.S. Treasury
Cash and Cash Equivalents [Line Items]
Amortized Cost		1,900,000
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		$ 1,900,000