Earnings Per Share - Computation of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Dec. 27, 2025	Dec. 28, 2024	Dec. 27, 2025	Dec. 28, 2024
Numerator:
Net income (loss) - basic	$ 78.2	$ (60.9)	$ 82.4	$ (143.3)
Net income (loss) - diluted	$ 78.2	$ (60.9)	$ 82.4	$ (143.3)
Denominator:
Weighted average common shares outstanding - basic (in shares)	71.1	68.9	70.7	68.6
Shares issuable assuming conversion of the convertible notes (in shares)	13.8	0.0	9.8	0.0
Weighted average common shares outstanding - diluted (in shares)	87.8	68.9	83.1	68.6
Net income (loss) per share:
Basic (in usd per share)	$ 1.10	$ (0.88)	$ 1.17	$ (2.09)
Diluted (in usd per share)	$ 0.89	$ (0.88)	$ 0.99	$ (2.09)
Shares Issuable to ESPP
Denominator:
Effect of dilutive securities from 2015 Equity Incentive Plan (in shares)	0.1	0.0	0.1	0.0
Employee stock options
Denominator:
Effect of dilutive securities from 2015 Equity Incentive Plan (in shares)	0.3	0.0	0.4	0.0
Shares Issuable Under RSUs and PSUs
Denominator:
Effect of dilutive securities from 2015 Equity Incentive Plan (in shares)	2.5	0.0	2.1	0.0