Segment Information (Reconciliation Of Company's Consolidated Segment Operating Income To Consolidated Income Before Income Taxes) (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Oct. 02, 2015	Sep. 30, 2016	Oct. 02, 2015
Segment Reporting Information [Line Items]
Consolidated operating income		$ 55.3	$ 46.0	$ 125.7	$ 121.5
Unallocated corporate expense (1)		(253.7)	(252.0)	(799.5)	(787.6)
Restructuring charges (2)	[1]	(4.0)	(3.0)	(11.0)	(9.8)
Stock-based compensation		(13.3)	(12.8)	(40.0)	(37.3)
Amortization of purchased intangible assets		(37.3)	(40.7)	(117.2)	(122.2)
Non-operating income (expense), net:		(3.1)	(2.5)	(5.8)	2.0
Consolidated income before taxes		52.2	43.5	119.9	123.5
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated operating income		127.9	122.2	352.8	350.9
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Unallocated corporate expense (1)	[2]	$ (18.0)	$ (19.7)	$ (58.9)	$ (60.1)

[1] Restructuring charges primarily consist of severance and benefits, resulting from employee headcount reductions in connection with the Company's restructuring programs related to decisions to streamline processes and reduce the cost structure. As of the end of the third quarter of fiscal 2016, the Company's restructuring liability was $2.6 million, which was expected to be settled by the third quarter of fiscal 2017. Restructuring liabilities are reported within Other current liabilities on the Condensed Consolidated Balance Sheets.

[2] Unallocated corporate expense includes general corporate expense, acquisition costs and executive transition costs.