Schedule of Expected Future Amortization Expense (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
2013 (remaining three months)	$ 1,506
2014	6,726
2015	6,888
2016	6,366
2017	5,774
Thereafter	19,573
Total	$ 46,833

Finite Lived Intangible Assets, Amortization Expense, Net

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- Definition

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 in the remainder of the fiscal year following the latest fiscal year ended 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 fifth 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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- Definition

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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- Definition

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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- Definition

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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