Segment Information (Reconciliation Of Company's Consolidated Segment Operating Income To Consolidated Income Before Income Taxes) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Apr. 01, 2016
Segment Reporting Information [Line Items]
Consolidated operating income	$ 56.6	$ 29.9
Unallocated corporate expense	(270.0)	(270.7)
Restructuring charges	(3.4)	(2.1)
Amortization of purchased intangible assets	(33.3)	(40.3)
Stock-based compensation	(13.7)	(13.7)
Amortization of acquisition-related inventory step-up	(0.1)
Acquisition and divestiture items	(2.1)	(1.6)
Executive transition costs		(0.9)
Non-operating income (expense), net:	9.0	(0.5)
Consolidated income before taxes	65.6	29.4
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated operating income	127.6	107.2
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Unallocated corporate expense	$ (18.4)	$ (18.7)

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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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

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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- Definition

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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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

+ References

No definition available.

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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- Definition

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

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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- Definition

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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