Schedule of Selected Operating Segment Financial Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Mar. 30, 2014
Segment Reporting Information [Line Items]
Restructuring, impairments, and other costs	$ (4.7)	$ (6.1)
Selling, general and administrative expense	(52.7)	(55.5)
Charge for litigation		(4.4)
Corporate research and development expense	(41.7)us-gaap_ResearchAndDevelopmentExpense	(41.1)us-gaap_ResearchAndDevelopmentExpense
Revenue	355.7us-gaap_Revenues	344.1us-gaap_Revenues
Operating income	6.2us-gaap_OperatingIncomeLoss	(7.1)us-gaap_OperatingIncomeLoss
Other expense, net	1.2us-gaap_NonoperatingIncomeExpense	1.1us-gaap_NonoperatingIncomeExpense
Income (loss) before income taxes	5.0	(8.2)
Corporate
Segment Reporting Information [Line Items]
Restructuring, impairments, and other costs	(4.7)	(6.1)
Accelerated depreciation on assets related to factory closure	(4.5)
Selling, general and administrative expense	(46.6)	(48.8)
Charge for litigation		(4.4)
Corporate research and development expense	(3.5)	(2.4)
SPS \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	211.2	203.4
Operating income	42.8	37.1
APSS \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	96.3	95.2
Operating income	11.5	8.4
SPG \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	48.2	45.5
Operating income	$ 11.2	$ 9.1

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

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Amount of increase (decrease) in loss contingency liability.

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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.

+ References

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-Publisher FASB

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-Topic 985

-SubTopic 20

-Section 50

-Paragraph 1

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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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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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-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

-Paragraph 2

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