Estimate of Future Patent Cost Amortization (Detail) (Patents [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Patents [Member]
Amortization Expense [Line Items]
Estimated Amortization expense, 2013	$ 15,917
Estimated Amortization expense, 2014	15,066
Estimated Amortization expense, 2015	13,618
Estimated Amortization expense, 2016	12,444
Estimated Amortization expense, 2017	11,296
Thereafter	$ 27,363

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Amount of amortization expense expected to be recognized after the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

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- Definition

Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ 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 (a)(3)

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

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Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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