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. 29, 2017	Sep. 30, 2016	Sep. 29, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Consolidated operating income	$ 64.0	$ 55.3	$ 183.2	$ 125.7
Unallocated corporate expense	(285.5)	(253.7)	(839.4)	(799.5)
Restructuring charges	(1.6)	(4.0)	(7.8)	(11.0)
Amortization of purchased intangible assets	(40.0)	(37.3)	(109.1)	(117.2)
Stock-based compensation	(16.1)	(13.3)	(45.0)	(40.0)
Amortization of acquisition-related inventory step-up	(2.2)	0.0	(2.8)	0.0
Acquisition and divestiture items	0.3	(0.9)	(6.1)	(3.4)
Executive transition costs	0.0	0.0	0.0	(1.0)
Non-operating income (expense), net:	5.6	(3.1)	19.6	(5.8)
Consolidated income before taxes	69.6	52.2	202.8	119.9
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated operating income	146.6	127.9	415.8	352.8
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Unallocated corporate expense	$ (23.0)	$ (17.1)	$ (61.8)	$ (54.5)

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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