Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 28, 2019	Dec. 29, 2018	May 29, 2018
Numerator:
Income from continuing operations	$ 28.0	$ 15.4	$ 34.8	$ 0.1
Loss from discontinued operations, net of taxes	0.0	(2.4)	0.0	(2.4)
Net income (loss)	$ 28.0	$ 13.0	$ 34.8	$ (2.3)
Weighted-average shares outstanding:
Basic (in shares)	230.0	228.3	229.7	227.8
Shares issuable assuming conversion of convertible notes (in shares)	5.1	0.0	4.0	0.0
Effect of dilutive securities from stock-based benefit plans (in shares)	3.2	2.1	3.7	2.7
Diluted (in shares)	238.3	230.4	237.4	230.5
Net income (loss) per share - basic:
Continuing operations (in dollars per share)	$ 0.12	$ 0.07	$ 0.15	$ 0.00
Discontinued operations (in dollars per share)	0	(0.01)	0	(0.01)
Net income (loss) per share - basic (in dollars per share)	0.12	0.06	0.15	(0.01)
Net income (loss) per share - diluted:
Continuing operations (in dollars per share)	0.12	0.07	0.15	0.00
Discontinued operations (in dollars per share)	0	(0.01)	0	(0.01)
Net income (loss) per share - diluted (in dollars per share)	$ 0.12	$ 0.06	$ 0.15	$ (0.01)
Anti-dilutive securities excluded from computation of earnings per share
Total potentially dilutive securities (in shares)	0.3	0.2	0.2	0.7
2024 Notes | Convertible Notes
Convertible notes
Interest rate on senior convertible notes	1.00%		1.00%
Conversion price of debt (in dollars per share)			$ 13.22
2023 Notes | Convertible Notes
Convertible notes
Interest rate on senior convertible notes	1.75%		1.75%		1.75%
Conversion price of debt (in dollars per share)			$ 13.94
Restricted stock units
Anti-dilutive securities excluded from computation of earnings per share
Total potentially dilutive securities (in shares)	0.3	0.2	0.2	0.7
Stock options and ESPP
Anti-dilutive securities excluded from computation of earnings per share
Total potentially dilutive securities (in shares)	0.0	0.1	0.0	0.1