Investments, Forward Contracts and Fair Value Measurements - Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Millions	Dec. 28, 2019	Jun. 29, 2019
Debt available-for-sale securities
Total debt available-for-sale securities	$ 0.5	$ 0.6
Money market funds	349.3	322.9
Trading securities	1.6	1.5
Foreign currency forward contract	5.9	1.2
Total assets	357.3	326.2
Liability:
Foreign currency forward contract	1.1	4.0
Contingent consideration	34.1	38.4
Total liabilities	35.2	42.4
Fair value of contingent consideration, current	0.8	0.7
Fair value of contingent consideration, noncurrent	33.3	37.7
Prepayments and other current assets
Debt available-for-sale securities
Total assets	5.9
Other current assets
Debt available-for-sale securities
Total assets		1.2
Cash and cash equivalents
Debt available-for-sale securities
Total assets	341.9	315.5
Short-term investments
Debt available-for-sale securities
Total assets	1.6	1.5
Restricted cash
Debt available-for-sale securities
Total assets	3.4	3.5
Other non-current assets
Debt available-for-sale securities
Total debt available-for-sale securities	0.5	0.6
Total assets	4.5	4.5
Other current liabilities
Liability:
Total liabilities	1.1	4.0
Asset-backed securities
Debt available-for-sale securities
Total debt available-for-sale securities	0.5	0.6
Level 1
Debt available-for-sale securities
Total debt available-for-sale securities	0.0	0.0
Money market funds	349.3	322.9
Trading securities	1.6	1.5
Foreign currency forward contract	0.0	0.0
Total assets	350.9	324.4
Liability:
Foreign currency forward contract	0.0	0.0
Contingent consideration	0.0	0.0
Total liabilities	0.0	0.0
Level 1 \| Asset-backed securities
Debt available-for-sale securities
Total debt available-for-sale securities	0.0	0.0
Level 2
Debt available-for-sale securities
Total debt available-for-sale securities	0.5	0.6
Money market funds	0.0	0.0
Trading securities	0.0	0.0
Foreign currency forward contract	5.9	1.2
Total assets	6.4	1.8
Liability:
Foreign currency forward contract	1.1	4.0
Contingent consideration	0.0	0.0
Total liabilities	1.1	4.0
Level 2 \| Asset-backed securities
Debt available-for-sale securities
Total debt available-for-sale securities	0.5	0.6
Level 3
Debt available-for-sale securities
Total debt available-for-sale securities	0.0	0.0
Money market funds	0.0	0.0
Trading securities	0.0	0.0
Foreign currency forward contract	0.0	0.0
Total assets	0.0	0.0
Liability:
Foreign currency forward contract	0.0	0.0
Contingent consideration	34.1	38.4
Total liabilities	34.1	38.4
Level 3 \| Asset-backed securities
Debt available-for-sale securities
Total debt available-for-sale securities	$ 0.0	$ 0.0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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