Subsequent Events (Details) - $ / shares shares in Millions			3 Months Ended		9 Months Ended
	Oct. 20, 2016	Jul. 21, 2016	Sep. 27, 2016	Sep. 29, 2015	Sep. 27, 2016	Sep. 29, 2015
Subsequent events
Cash dividends declared per common share (in dollars per share)		$ 0.24	$ 0.24	$ 0.20	$ 0.64	$ 0.53
Subsequent events
Subsequent events
Cash dividends declared per common share (in dollars per share)	$ 0.24
Treasury Stock
Subsequent events
Number of shares authorized to be repurchased		56