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Shareholders' Equity (Narrative) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Sep. 28, 2018	Jun. 29, 2018	Mar. 30, 2018	Nov. 30, 2017
Two Thousand Seventeen Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock repurchase program approved amount				$ 600.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 392.2
Retained Earnings [Member]
Equity, Class of Stock [Line Items]
Stock Repurchased During Period, Value			$ 42.5
Open Market Purchases [Member] \| Two Thousand Seventeen Stock Repurchase Program [Member]
Equity, Class of Stock [Line Items]
Stock Repurchased During Period, Shares	0.0	0.0	1.3
Accelerated Share Repurchases, Final Price Paid Per Share			$ 39.43
Stock Repurchased During Period, Value			$ 50.0