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Shareholders' Equity (Narrative) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 29, 2019	Mar. 30, 2018	Nov. 30, 2017
Equity, Class of Stock [Line Items]
Stock Repurchased During Period, Value	$ 40.0	$ 50.0
Two Thousand Seventeen Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	312.2
Retained Earnings [Member]
Equity, Class of Stock [Line Items]
Stock Repurchased During Period, Value	$ 33.5	$ 42.5
Maximum \| Two Thousand Seventeen Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock repurchase program approved amount			$ 600.0
Open Market Purchases [Member] \| Two Thousand Seventeen Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock Repurchased During Period, Shares	1.0
Accelerated Share Repurchases, Final Price Paid Per Share	$ 39.59
Stock Repurchased During Period, Value	$ 40.0