Net Income Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2015	Jun. 28, 2014	Jun. 27, 2015	Jun. 28, 2014
Net Income Per Common Share [Line Items]
Net income	$ 62.0	$ 47.6	$ 91.5	$ 99.8
Weighted-average shares of common stock outstanding	49.8	50.2	49.8	50.2
Common equivalent shares:
Assumed exercise of dilutive options, restricted shares, restricted stock units and performance share units	0.6	0.9	0.5	0.9
Weighted-average common and common equivalent shares outstanding	50.4	51.1	50.3	51.1
Basic earnings per share	$ 1.24	$ 0.95	$ 1.84	$ 1.99
Diluted earnings per share	$ 1.23	$ 0.93	$ 1.82	$ 1.95
Shares excluded from the determination of potential common stock because inclusion would have been anti-dilutive	0.7	0.4	0.7	0.4