Fair Value Measurements - Schedule of Fair Value Measurements (Details) - USD ($) $ in Millions	Oct. 03, 2020	Jun. 27, 2020	Jun. 29, 2019
Assets:
Total debt available-for-sale securities	$ 0.5	$ 0.5	$ 0.5
Money market funds	347.7		334.6
Trading securities	1.5		1.4
Foreign currency forward contracts	8.0		2.2
Total assets	357.7		338.7
Liability:
Foreign currency forward contracts	1.5		1.5
Fair value of contingent consideration	9.9	9.9	9.9
Total liabilities	11.4		11.4
Fair value of contingent consideration, noncurrent	8.9	9.4
Fair value of contingent consideration, current	1.0	0.5
Level 1
Assets:
Total debt available-for-sale securities	0.0		0.0
Money market funds	347.7		334.6
Trading securities	1.5		1.4
Foreign currency forward contracts	0.0		0.0
Total assets	349.2		336.0
Liability:
Foreign currency forward contracts	0.0		0.0
Fair value of contingent consideration	0.0		0.0
Total liabilities	0.0		0.0
Level 2
Assets:
Total debt available-for-sale securities	0.5		0.5
Money market funds	0.0		0.0
Trading securities	0.0		0.0
Foreign currency forward contracts	8.0		2.2
Total assets	8.5		2.7
Liability:
Foreign currency forward contracts	1.5		1.5
Fair value of contingent consideration	0.0		0.0
Total liabilities	1.5		1.5
Level 3
Assets:
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 contracts	0.0		0.0
Total assets	0.0		0.0
Liability:
Foreign currency forward contracts	0.0		0.0
Fair value of contingent consideration	9.9		9.9
Total liabilities	9.9		9.9
Asset-backed securities
Assets:
Total debt available-for-sale securities	0.5	0.5	0.5
Asset-backed securities \| Level 1
Assets:
Total debt available-for-sale securities	0.0		0.0
Asset-backed securities \| Level 2
Assets:
Total debt available-for-sale securities	0.5		0.5
Asset-backed securities \| Level 3
Assets:
Total debt available-for-sale securities	0.0		$ 0.0
Prepayments and other current assets
Assets:
Total assets	8.0	2.2
Cash and cash equivalents
Assets:
Total assets	340.2	327.2
Short-term investments
Assets:
Total assets	1.5	1.4
Restricted cash
Assets:
Total assets	3.2	3.4
Other non-current assets
Assets:
Total debt available-for-sale securities	0.5	0.5
Total assets	4.8	4.5
Other current liabilities
Liability:
Total liabilities	$ 1.5	$ 1.5

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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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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Fair value of financial and nonfinancial obligations.

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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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