v2.4.0.6

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Finite-Lived Intangible Assets [Line Items]
Impairment of goodwill, intangible assets and other long-lived assets	$ 0	$ 0	$ 0	$ 0
Warranty period, minimum, long-term sales agreement			3 years
Warranty period, maximum, long-term sales agreement			6 years
Options to purchase of shares of common stock	6.4	5.0	6.4	4.1
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Total renewal costs capitalized	100,000		300,000
Weighted average number of years until the next renewal			1 year
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Total renewal costs capitalized	$ 25,000		$ 48,000
Weighted average number of years until the next renewal			6 years
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Warranty period for defects in material and workmanship			6 months
Product life estimate			3 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Warranty period for defects in material and workmanship			1 year
Product life estimate			6 years

X

- Definition

Long-term sales agreement warranty maximum.

+ References

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- Definition

Long-term sales agreement warranty minimum.

+ References

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- Definition

Estimated useful life of products.

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- Definition

Warranty period for defects in material and workmanship.

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 07-4

-Paragraph 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Contingent Stock Agreement

-URI http://asc.fasb.org/extlink&oid=6508534



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Antidilution

-URI http://asc.fasb.org/extlink&oid=6505113



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 171

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 40

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257



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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 13, 14

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- Definition

The amount of capitalized costs incurred in the period to renew or extend the term of a recognized finite-lived (amortizing and amortizable) intangible asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275



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-Name FASB Staff Position (FSP)

-Number FAS142-3

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-Appendix A1



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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Weighted average period before the next renewal or extension (both explicit and implicit) for intangible assets that have been renewed or extended, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

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-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

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- Definition

Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

+ References

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