Cash, Cash Equivalents and Short-Term Investments - Schedule of cash, cash equivalents and short-term investments (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 24, 2022	Jun. 25, 2022
Cash and Cash Equivalents [Line Items]
Amortized Cost	$ 41.8	$ 54.0
Corporate Debt Securities [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	35.8	43.7
Unrealized Gain (Loss) on Investments	(1.6)	(1.9)
Assets, Fair Value Adjustment	34.2	41.8
Cash [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	321.4	811.9
Unrealized Gain (Loss) on Investments	0.0	0.0
Assets, Fair Value Adjustment	321.4	811.9
Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	440.0	12.1
Unrealized Gain (Loss) on Investments	0.0	0.0
Assets, Fair Value Adjustment	440.0	12.1
Certificates of Deposit [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	57.4	2.4
Unrealized Gain (Loss) on Investments	0.0	0.0
Assets, Fair Value Adjustment	57.4	2.4
Certificate of Deposit [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	1.1
Municipal Bonds [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	4.9	7.9
Unrealized Gain (Loss) on Investments	(0.1)	(0.1)
Assets, Fair Value Adjustment	4.8	7.8
Cash and Cash Equivalents [Member]
Cash and Cash Equivalents [Line Items]
Amortized Cost	818.8	824.0
Unrealized Gain (Loss) on Investments	0.0	0.0
Assets, Fair Value Adjustment	818.8	824.0
Short-Term Investments [Member]
Cash and Cash Equivalents [Line Items]
Unrealized Gain (Loss) on Investments	(1.7)	(2.0)
Assets, Fair Value Adjustment	40.1	$ 52.0
Short-Term Investments [Member] \| Certificates of Deposit [Member]
Cash and Cash Equivalents [Line Items]
Unrealized Gain (Loss) on Investments	0.0
Assets, Fair Value Adjustment	$ 1.1

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Amortized cost 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of unrealized gain (loss) on investment.

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