Investments, Forward Contracts and Fair Value Measurements - Measured at Fair Value (Details) - USD ($) $ in Millions	Sep. 28, 2019	Jun. 29, 2019
Debt available-for-sale securities
Total debt available-for-sale securities	$ 0.6	$ 0.6
Money market funds	336.1	322.9
Trading securities	1.5	1.5
Foreign currency forward contract	2.0	1.2
Total assets	340.2	326.2
Liability:
Foreign currency forward contract	4.6	4.0
Contingent consideration	40.1	38.4
Total liabilities	44.7	42.4
Fair value of contingent consideration, current	1.7	0.7
Fair value of contingent consideration, noncurrent	38.4	37.7
Prepayments and other current assets
Debt available-for-sale securities
Total assets	2.0
Other current assets
Debt available-for-sale securities
Total assets		1.2
Cash and cash equivalents
Debt available-for-sale securities
Total assets	328.7	315.5
Short-term investments
Debt available-for-sale securities
Total assets	1.5	1.5
Restricted cash
Debt available-for-sale securities
Total assets	3.5	3.5
Other non-current assets
Debt available-for-sale securities
Total assets	4.5	4.5
Other current liabilities
Liability:
Total liabilities	4.6	4.0
Asset-backed securities
Debt available-for-sale securities
Total debt available-for-sale securities	0.6	0.6
Level 1
Debt available-for-sale securities
Total debt available-for-sale securities	0.0	0.0
Money market funds	336.1	322.9
Trading securities	1.5	1.5
Foreign currency forward contract	0.0	0.0
Total assets	337.6	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	0.6	0.6
Money market funds	0.0	0.0
Trading securities	0.0	0.0
Foreign currency forward contract	2.0	1.2
Total assets	2.6	1.8
Liability:
Foreign currency forward contract	4.6	4.0
Contingent consideration	0.0	0.0
Total liabilities	4.6	4.0
Level 2 \| Asset-backed securities
Debt available-for-sale securities
Total debt available-for-sale securities	0.6	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	40.1	38.4
Total liabilities	40.1	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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