Shareholders' Equity (Narrative) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2016	Oct. 02, 2015	Jan. 01, 2016	Sep. 30, 2015	Aug. 31, 2015	Aug. 31, 2014
Equity, Class of Stock [Line Items]
Stock Repurchased During Period, Shares		7.5
Common Stock Acquired, Average Cost Per Share		$ 21.29
2014 Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock repurchase program approved amount						$ 300.0
Stock Repurchased During Period, Shares		84.3
2015 Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock repurchase program approved amount					$ 400.0
Stock Repurchased During Period, Shares	4.2	75.1
Common Stock Acquired, Average Cost Per Share	$ 24.20
Stock Repurchased During Period, Value	$ 102.2
Stock Repurchase Program, Remaining Authorized Repurchase Amount	147.7
Retained Earnings [Member]
Equity, Class of Stock [Line Items]
Stock Repurchased During Period, Value	$ 80.8
Repurchase Agreements [Member] | 2015 Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock repurchase program approved amount				$ 75.0
Stock Repurchased During Period, Shares			3.7
Accelerated Share Repurchases, Final Price Paid Per Share			$ 20.11