Net Income Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013
Net income per common share amounts
Income from continuing operations	$ 65.0	$ 62.0	$ 181.0	$ 199.6
Loss from discontinued operations, net of tax	(0.7)	(15.5)	(3.0)	(26.5)
Net income	$ 64.3	$ 46.5	$ 178.0	$ 173.1
Weighted-average number of common shares outstanding	93.3	97.9	94.7	99.1
Dilutive shares (additional common shares issuable under stock-based awards)	1.9	1.7	1.9	1.6
Weighted-average number of common shares outstanding, assuming dilution	95.2	99.6	96.6	100.7
Net income (loss) per common share:
Continuing operations (in dollars per share)	$ 0.70	$ 0.63	$ 1.91	$ 2.01
Discontinued operations (in dollars per share)	$ (0.01)	$ (0.16)	$ (0.03)	$ (0.26)
Net income per common share (in dollars per share)	$ 0.69	$ 0.47	$ 1.88	$ 1.75
Net income (loss) per common share, assuming dilution:
Continuing operations (in dollars per share)	$ 0.68	$ 0.62	$ 1.87	$ 1.98
Discontinued operations (in dollars per share)		$ (0.15)	$ (0.03)	$ (0.26)
Net income per common share, assuming dilution (in dollars per share)	$ 0.68	$ 0.47	$ 1.84	$ 1.72
Stock-based compensation awards excluded from the computation of net income per common share, assuming dilution	3	5	3	6