Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended		6 Months Ended
	Aug. 17, 2015	Dec. 31, 2016	Jan. 02, 2016	Dec. 31, 2016	Jan. 02, 2016	Aug. 21, 2013
Numerator:
Income (loss) from continuing operations, net of taxes		$ 49.2	$ 1.0	$ 127.2	$ (14.7)
Income (loss) from discontinued operations, net of taxes		0.0	3.0	0.0	(50.4)
Net income (loss)		$ 49.2	$ 4.0	$ 127.2	$ (65.1)
Denominator:
Weighted-average number of common shares outstanding - basic (in shares)		230.5	234.9	231.4	235.5
Effect of dilutive securities from stock-based benefit plans (in shares)		3.7	2.2	4.4	0.0
Shares used in per share calculation - diluted (in shares)		234.2	237.1	235.8	235.5
Net income (loss) per share from - basic:
Continuing operations (in dollars per share)		$ 0.21	$ 0.01	$ 0.55	$ (0.06)
Discontinued operations (in dollars per share)		0.00	0.01	0.00	(0.22)
Net (loss) income per share (in dollars per share)		0.21	0.02	0.55	(0.28)
Net income (loss) per share from - diluted:
Continuing operations (in dollars per share)		0.21	0.01	0.54	(0.06)
Discontinued operations (in dollars per share)		0.00	0.01	0.00	(0.22)
Net income (loss) per share (in dollars per share)		$ 0.21	$ 0.02	$ 0.54	$ (0.28)
Anti-dilutive securities excluded from computation of earnings per share
Total potentially dilutive securities (in shares)		1.7	5.4	1.6	14.4
2033 Notes
Convertible notes
Interest rate on senior convertible notes (as a percent)		0.625%		0.625%		0.625%
Conversion price of debt (in dollars per share)	$ 11.28			$ 11.28
Stock options and ESPP
Anti-dilutive securities excluded from computation of earnings per share
Total potentially dilutive securities (in shares)		1.5	0.9	1.6	3.4
Restricted Stock Units
Anti-dilutive securities excluded from computation of earnings per share
Total potentially dilutive securities (in shares)		0.2	4.5	0.0	11.0