Schedule of Selected Operating Segment Financial Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 27, 2016	Mar. 29, 2015
Segment Reporting Information [Line Items]
Restructuring, impairments, and other costs	$ 10.9	$ (4.7)
Selling, general and administrative expense	(48.6)	(52.7)
Corporate research and development expense	(40.1)	(41.7)
Revenue	327.0	355.7
Operating income	20.4	6.2
Other expense, net	1.6	1.2
Income before income taxes	18.8	5.0
Corporate
Segment Reporting Information [Line Items]
Restructuring, impairments, and other costs	10.9	(4.7)
Accelerated depreciation on assets related to factory closures		(4.5)
Selling, general and administrative expense	(40.8)	(46.6)
Acquisition-related costs	(5.5)
Corporate research and development expense	(3.9)	(3.5)
SPS \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	205.7	211.2
Operating income	41.7	42.8
APSS \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	76.4	96.3
Operating income	8.1	11.5
SPG \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	44.9	48.2
Operating income	$ 9.9	$ 11.2

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.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 10
-Article 5

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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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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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-Publisher FASB
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Amount of accelerated depreciation charged against earnings associated with exit from or disposal of business activities or restructuring plan.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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-Publisher FASB
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