Net Income per Share (Details 2) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended			3 Months Ended		9 Months Ended
	Oct. 23, 2014	Feb. 13, 2014	Aug. 10, 2012	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013
Share Repurchase Program
Share repurchase program, amount authorized to be repurchased	$ 30.0	$ 15.0	$ 5.0
Number of shares repurchased and retired				279,094	33,775	531,694	33,775
Average repurchase price per share (in dollars per share)				$ 25.73	$ 18.70	$ 23.91	$ 18.70
Amount available for future repurchases						$ 3.7