Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014	Sep. 21, 2015	Dec. 31, 2014	May. 20, 2014
Stockholders Equity Note Disclosure [Line Items]
Treasury Stock, Shares, Retired			19.1
Common Stock, Dividends, Per Share, Cash Paid	$ 0.32	$ 0.30	$ 0.96	$ 0.80
Share repurchase (in shares)			3.1
Repurchase of common stock, value			$ 200.0	$ 850.0
Dividends payable amount (USD per share)	$ 0.32	$ 0.30	$ 0.32	$ 0.30	$ 0.32	$ 0.30	$ 1.20
Dividends Payable, Amount Per Share, Quarterly Dividends Declared						0.32	$ 0.30
Dividends Payable, Amount Per Share, Increase (Decrease) in Quarterly Dividends Declared						$ 0.02
Dividends payable	$ 57.7		$ 57.7			$ 116.8
December 2014 Share Repurchase Program [Member]
Stockholders Equity Note Disclosure [Line Items]
Repurchase of shares of our common stock up to a maximum aggregate value	1,000.0		$ 1,000.0
Common stock authorized for repurchase, expiration date			Dec. 31, 2019
Share repurchase program remaining available amount	$ 800.0		$ 800.0