Investments - Contractual Maturities of Marketable Investments (Details) - USD ($) $ in Millions	Sep. 25, 2022	Jun. 26, 2022
Debt Securities, Available-for-sale [Line Items]
Within One Year	$ 206.2
After One, Within Five Years	418.6
After Five, Within Ten Years	14.7
After Ten Years	36.1
Total	675.6	$ 749.3
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Within One Year	124.5
After One, Within Five Years	292.4
After Five, Within Ten Years	0.0
After Ten Years	0.0
Total	416.9	448.0
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Within One Year	52.3
After One, Within Five Years	98.4
After Five, Within Ten Years	0.0
After Ten Years	0.0
Total	150.7	162.2
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Within One Year	29.4
After One, Within Five Years	25.9
After Five, Within Ten Years	0.0
After Ten Years	0.0
Total	55.3	65.8
Variable rate demand notes
Debt Securities, Available-for-sale [Line Items]
Within One Year	0.0
After One, Within Five Years	0.0
After Five, Within Ten Years	14.7
After Ten Years	36.1
Total	50.8	69.4
U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Within One Year	0.0
After One, Within Five Years	1.9
After Five, Within Ten Years	0.0
After Ten Years	0.0
Total	$ 1.9	$ 3.9