Cash, Cash Equivalents, and Short-term Investments - Summary of Cash and Cash Equivalents (Details) - USD ($) $ in Millions	Dec. 30, 2017	Jul. 01, 2017	Dec. 31, 2016	Jul. 02, 2016
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 202.1	$ 272.9	$ 155.9	$ 157.1
Cash
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	133.2	201.3
Certificates of deposit
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	6.2	52.1
Commercial paper
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	41.9	14.7
Corporate debt securities
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	2.7	0.0
Money market funds
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	3.0	4.8
U.S. Treasury
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	13.5	0.0
Asset-backed securities
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 1.6	$ 0.0